Oncolytic vaccinia virus cancer therapy

ABSTRACT

Embodiments of the invention are directed methods that include a thymidine kinase deficient vaccinia virus. The methods include administering the vaccinia virus at increased viral concentrations. Further aspects of the invention include methods for inducing oncolysis or collapse of tumor vasculature in a subject having a tumor comprising administering to a subject at least 1×10 8  infectious viral particles of a TK-deficient, GM-CSF-expressing, replication-competent vaccinia virus vector sufficient to induce oncolysis of cells in the tumor.

I. CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No.13/535,291, filed Jun. 27, 2012, which is a continuation-in-part of U.S.patent application Ser. No. 12/531,353, filed May 11, 2010 which is theU.S. national stage of International Application PCT/US08/57257, filedMar. 17, 2008 and which claims the benefit of U.S. Provisional PatentApplication No. 60/894,932, filed Mar. 15, 2007 and is acontinuation-in-part of U.S. patent application Ser. No. 11/470,951,filed Sep. 7, 2006 which claims the benefit of U.S. ProvisionalApplication No. 60/714,979, filed Sep. 7, 2005, the disclosures of whichare incorporated herein by reference in their entireties.

II. FIELD OF THE INVENTION

The present invention relates generally to the fields of oncology andvirology. More particularly, it concerns poxviruses, specificallyincluding oncolytic vaccinia viruses suitable for the treatment ofcancer.

III. BACKGROUND OF THE INVENTION

Normal tissue homeostasis is a highly regulated process of cellproliferation and cell death. An imbalance of either cell proliferationor cell death can develop into a cancerous state (Solyanik et aL, 1995;Stokke et al., 1997; Mumby and Walter, 1991; Natoli et al., 1998;Magi-Galluzzi et al., 1998). For example, cervical, kidney, lung,pancreatic, colorectal, and brain cancer are just a few examples of themany cancers that can result (Erlandsson, 1998; Kolmel, 1998; Mangrayand King, 1998; Mougin et al., 1998). In fact, the occurrence of canceris so high that over 500,000 deaths per year are attributed to cancer inthe United States alone.

The maintenance of cell proliferation and cell death is at leastpartially regulated by proto-oncogenes and tumor suppressors. Aproto-oncogene or tumor suppressor can encode proteins that inducecellular proliferation (e.g., sis, erbB, src, ras and myc), proteinsthat inhibit cellular proliferation (e.g., Rb, p16, p19, p21, p53, NF1and WT1) or proteins that regulate programmed cell death (e.g., bcl-2)(Ochi et al., 1998; Johnson and Hamdy, 1998; Liebermann et al., 1998).However, genetic rearrangements or mutations of these proto-oncogenesand tumor suppressors result in the conversion of a proto-oncogene intoa potent cancer-causing oncogene or of a tumor suppressor into aninactive polypeptide. Often, a single point mutation is enough toachieve the transformation. For example, a point mutation in the p53tumor suppressor protein results in the complete loss of wild-type p53function (Vogelstein and Kinzler, 1992).

Currently, there are few effective options for the treatment of manycommon cancer types. The course of treatment for a given individualdepends on the diagnosis, the stage to which the disease has developedand factors such as age, sex, and general health of the patient. Themost conventional options of cancer treatment are surgery, radiationtherapy and chemotherapy. Surgery plays a central role in the diagnosisand treatment of cancer. Typically, a surgical approach is required forbiopsy and to remove cancerous growth. However, if the cancer hasmetastasized and is widespread, surgery is unlikely to result in a cureand an alternate approach must be taken.

Radiation therapy and chemotherapy are the most common alternatives tosurgical treatment of cancer (Mayer, 1998; Ohara, 1998; Ho et al.,1998). Radiation therapy involves a precise aiming of high energyradiation to destroy cancer cells and much like surgery, is mainlyeffective in the treatment of non-metastasized, localized cancer cells.Side effects of radiation therapy include skin irritation, difficultyswallowing, dry mouth, nausea, diarrhea, hair loss, and loss of energy(Curran, 1998; Brizel, 1998). Chemotherapy, the treatment of cancer withanti-cancer drugs, is another mode of cancer therapy, and mostchemotherapy approaches include the combination of more than oneanti-cancer drug, which has proven to increase the response rate of awide variety of cancers (U.S. Pat. No. 5,824,348; U.S. Pat. No.5,633,016 and U.S. Pat. No. 5,798,339, incorporated herein byreference). However, a major side effect of chemotherapy drugs is thatthey also affect normal tissue cells, with the cells most likely to beaffected being those that divide rapidly in some cases (e.g., bonemarrow, gastrointestinal tract, reproductive system and hair follicles).Other toxic side effects of chemotherapy drugs can include sores in themouth, difficulty swallowing, dry mouth, nausea, diarrhea, vomiting,fatigue, bleeding, hair loss, and infection.

Immunotherapy, a rapidly evolving area in cancer research, is yetanother option for the treatment of certain types of cancers.Theoretically, the immune system may be stimulated to identify tumorcells as being foreign and targets them for destruction. Unfortunately,the response typically is not sufficient to prevent most tumor growth.However, recently there has been a focus in the area of immunotherapy todevelop methods that augment or supplement the natural defense mechanismof the immune system. Examples of immunotherapies currently underinvestigation or in use are immune adjuvants (e.g., Mycobacterium bovis,Plasmodium falciparum, dinitrochlorobenzene and aromatic compounds)(U.S. Pat. Nos. 5,801,005 and 5,739,169; Hui and Hashimoto, 1998;Christodoulides et al., 1998), cytokine therapy (e.g., interferons(IL-1, GM-CSF and TNF) (Bukowski et al., 1998; Davidson et al., 1998;Hellstrand et al., 1998), and gene therapy (e.g., TNF, IL-1, IL-2, p53)(Qin et al., 1998; Austin-Ward and Villaseca, 1998; U.S. Pat. Nos.5,830,880 and 5,846,945) and monoclonal antibodies (e.g.,anti-ganglioside GM2, anti-HER-2, anti-p185) (Pietras et al., 1998;Hanibuchi et al., 1998; U.S. Pat. No. 5,824,311). Such methods, whileshowing some promise, have demonstrated limited success.

Replication-selective oncolytic viruses hold promise for the treatmentof cancer (Kirn et al., 2001). These viruses can cause tumor cell deaththrough direct replication-dependent and/or viral geneexpression-dependent oncolytic effects (Kirn et al., 2001). In addition,viruses are able to enhance the induction of cell-mediated antitumoralimmunity within the host (Todo et al., 2001; Sinkovics et al., 2000).These viruses also can be engineered to expressed therapeutic transgeneswithin the tumor to enhance antitumoral efficacy (Hermiston, 2000).

However, major limitations exist to this therapeutic approach. Althougha degree of natural tumor-selectivity can be demonstrated for some virusspecies, new approaches are still needed to engineer and/or enhancetumor-selectivity for oncolytic viruses in order to maximize safety.This selectivity will become particularly important when intravenousadministration is used, and when potentially toxic therapeutic genes areadded to these viruses to enhance antitumoral potency; gene expressionwill need to be tightly limited in normal tissues. In addition,increased antitumoral potency through additional mechanisms such asinduction of antitumoral immunity or targeting of the tumor-associatedvasculature is highly desirable

Therefore, more effective and less toxic therapies for the treatment ofcancer are needed. The use of oncolytic viruses presents a potentialarea for development, however, the limitations discussed above need tobe overcome. The present invention addresses these limitations.

SUMMARY OF THE INVENTION

Embodiments of the invention are directed to methods that includeadministration of a thymidine kinase deficient vaccinia virus. Themethods include administering the vaccinia virus at increased viralconcentrations. In certain aspects, the methods include inducingoncolysis or collapse of tumor vasculature in a subject having a tumorcomprising administering to said subject at least 1×10⁸ infective viralparticles of a TK-deficient, granulocyte-macrophage colony stimulatingfactor (GM-CSF)-expressing, replication-competent vaccinia virus vectorsufficient to induce oncolysis of cells in the tumor. Preferably, thevirus vector has an expression region with a promoter directingexpression of a nucleic acid encoding human GM-CSF. In a further aspectof the invention, the methods can exclude pre-treatment of a subjectwith a vaccinia vaccine, e.g., a subject need not be vaccinated 1, 2, 3,4, 5, or more days, weeks, months, or years before administering thetherapy described herein. In some aspects, non-injected tumors or cancerwill be infected with the therapeutic virus, thus treating a patient byboth local administration and systemic dissemination. In some aspects,the virus vector is administered intravascularly, i.e. intravenously orintraarterially.

In certain aspects, the subject is administered one or more doses ofinfectious viral particles or plaque forming units (pfu), each dosecontaining at least 2×10⁸, 5×10⁸, 1×10⁹ 2×10⁹, 5×10⁹, 1×10¹⁰, 5×10¹⁰,1×10¹¹, 5×10¹¹, 1×10¹², 5×10¹², 1×10¹³ or more infectious viralparticles or plaque forming units (pfu), including the various valuesand ranges there between. For example, the subject may be administeredone or more doses of between about 1×10⁸ and 1×10¹², between about 1×10⁸and 1×10¹⁰, between about 1×10⁹ and 1×10¹² or between 1×10⁹ and 1×10¹⁰pfu of virus. In one aspect, a pharmaceutical composition comprising apharmaceutically acceptable carrier and a single dose of at least 2×10⁸,5×10⁸, 1×10⁹ 2×10⁹, 5×10⁹, 1×10¹⁰, 5×10¹⁰, 1×10¹¹, 5×10¹¹, 1×10¹²,5×10¹², 1×10¹³ or more infectious viral particles or plaque formingunits (pfu), including the various values and ranges there between isadministered one or more times to the subject. The viral dose can beadministered in 0.1, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10 or more mL, includingall values and ranges there between. In one aspect, the dose issufficient to generate a detectable level of GM-CSF in serum of thepatient, e.g., at least about, at most about or about 5, 10, 40, 50,100, 200, 500, 1,000, 5,000, 10,000, 15,000 to 20,000 pg/mL, includingall values and ranges there between. It is contemplated that a singledose of virus refers to the amount administered to a subject or a tumorover a 1, 2, 5, 10, 15, 20, or 24 hour period. The dose may be spreadover time or by separate injection. Typically, multiple doses areadministered to the same general target region, such as in the proximityof a tumor or in the case of intravenous administration a particularentry point in the blood stream or lymphatic system of a subject. Incertain aspects, the viral dose is delivered by injection apparatuscomprising a needle providing multiple ports in a single needle ormultiple prongs coupled to a syringe, or a combination thereof. In afurther aspect, multiple doses (2, 3, 4, 5, 6 or more doses) of thevaccinia virus are administered to the subject, for example, wherein asecond treatment occurs within 1, 2, 3, 4, 5, 6, 7 days or weeks of afirst treatment, or wherein the second treatment occurs within 2 weeksof the first treatment. In a related aspect, multiple doses of thevaccinia virus are administered to the subject over a period of 1, 2, 3,4, 5, 6, 7 or more days or weeks.

In certain embodiments the subject is a human. The subject may beafflicted with cancer and/or a tumor in which case the vaccinia virusvector is administered to treat the cancer and/or tumor. In certainembodiments the tumor may be non-resectable prior to treatment andresectable following treatment. In certain aspects the tumor is locatedon or in the liver. In other aspects, the tumor can be a brain cancertumor, a head and neck cancer tumor, an esophageal cancer tumor, a skincancer tumor, a lung cancer tumor, a thymic cancer tumor, a stomachcancer tumor, a colon cancer tumor, a liver cancer tumor, an ovariancancer tumor, a uterine cancer tumor, a bladder cancer tumor, atesticular cancer tumor, a rectal cancer tumor, a breast cancer tumor,or a pancreatic cancer tumor. In other embodiments the tumor is abladder tumor. In still further embodiments the tumor is melanoma. Thetumor can be a recurrent, primary, metastatic, and/or multi-drugresistant tumor. In certain embodiments, the tumor is a hepatocellulartumor or a metastasized tumor originating from another tissue orlocation. In certain aspects the tumor is in the liver.

In certain aspects, the method further comprises administering to thesubject a second cancer therapy. The second cancer therapy can bechemotherapy, biological therapy, radiotherapy, immunotherapy, hormonetherapy, anti-vascular therapy, cryotherapy, toxin therapy and/orsurgery, including combinations thereof. In a further aspect, thechemotherapy can be taxol or sorafenib. In still a further aspect,surgery includes the transarterial chemoembolization (TACE procedure,see Vogl et al., European Radiology 16(6):1393, 2005). The method mayfurther comprise a second administration of the vaccinia virus vector.Methods of the invention can further comprise assessing tumor cellviability before, during, after treatment, or a combination thereof. Incertain embodiments the virus is administered intravascularly,intratumorally, or a combination thereof. In a further aspectadministration is by injection into a tumor mass. In still a furtherembodiment, administration is by injection into or in the region oftumor vasculature. In yet a further embodiment, administration is byinjection into the lymphatic or vasculature system regional to saidtumor. In certain aspects the method includes imaging the tumor prior toor during administration. In certain aspects, a patient is or is notpre-immunized with a vaccinia virus vaccine. In a further aspect, thesubject can be immunocompromised, either naturally or clinically.

In certain aspects, the virus is administered in an amount sufficient toinduce oncolysis in at least 20% of cells in an injected tumor, in atleast 30% of cells in an injected tumor, in at least 30% of cells in aninjected tumor, in at least 40% of cells in an injected tumor, in atleast 50% of cells in an injected tumor tumor, in at least 60% of cellsin an injected tumor, in at least 70% of cells in an injected tumor, inat least 80% of cells in an injected tumor, or in at least 90% of cellsin an injected tumor.

In certain embodiments, the vaccinia virus may have a mutation in a geneencoding (a) vaccinia virus growth factor; (b) a functionalinterferon-modulating polypeptide, wherein the interferon-modulatingpolypeptide directly binds interferon; (c) a complement controlpolypeptide, wherein the mutation results in the virus lacking at leastone functional complement control polypeptide; (d) a TNF-modulatingpolypeptide, wherein the mutation results in the virus lacking at leastone functional TNF-modulating polypeptide; (e) a serine proteaseinhibitor, wherein the mutation results in the virus lacking at leastone functional serine protease inhibitor; (f) an IL-1β modulatorpolypeptide, wherein the mutation results in the virus lacking at leastone functional IL-1β modulator polypeptide; (g) a functional A41L, B7R,N1L or vCKBP chemokine binding polypeptide or C11R EGF-like polypeptide,wherein the mutation results in the virus lacking at least one functionof A41L, B7R, N1L, vCKBP, or C11R; or (h) a polypeptide, wherein themutation results in an increase in infectious EEV form of vacciniavirus. The vaccinia virus may be the Wyeth or Western Reserve (WR)strain. The promoter may be a vaccinia virus promoter, a syntheticpromoter, a promoter that directs transcription during at least theearly phase of infection, or a promoter that directs transcriptionduring at least the late phase of infection

In related embodiments, the vaccinia virus comprises one or moremodified viral genes. The one or more modified viral genes may compriseone or more of (a) an interferon-modulating polypeptide; (b) acomplement control polypeptide; (c) a TNF or chemokine-modulatingpolypeptide; (d) a serine protease inhibitor; (e) a IL-1β modulatingpolypeptide; (f) a non-infectious EEV form polypeptide; (g) a viralpolypeptide that act to inhibit release of infectious virus from cells(anti-infectious virus form polypeptide) or combinations thereof.

In another embodiment, there is provided a method for treating cancer ina subject or treating one or more metastases in a subject comprisingadministering to the subject at least 1×10⁸ infective viral particles ofa TK-deficient replicative vaccinia virus having an expression regionwith a promoter directing expression of a nucleic acid encodinggranulocyte-macrophage colony stimulating factor (GM-CSF). In relatedembodiments, the administration is intravascular.

In other embodiments, it is contemplated that methods involving areplication-competent vaccinia virus may contain a nucleic acid encodinga protein or RNA other than GM-CSF. In particular embodiments, thenucleic acid encodes another cytokine. In certain embodiments, thenucleic acid encodes other immunostimulatory cytokines or chemokines,such as IL-12, IL-2 and others. In additional embodiments, the nucleicacid may encode thymidine deaminase or tumor necrosis factor (TNF), suchas TNF-α. Moreover, it is contemplated that replicative vaccinia virusesmay express more than one heterologous sequence. It may express, forexample, GM-CSF protein and another protein or RNA molecule.

Embodiments of the invention target common, critical cancer pathways.Targeting these pathways involves the modulation of various cellularmechanisms (e.g., cellular thymidine kinase levels: E2F-responsive;EGF-R pathway activation; immune sanctuary: anti-viral IFN response(ras, p53); VEGF-induced vascular pore size: deposition IV) leading tomultiple efficacy mechanisms, such as oncolysis: necrosis, vascularshut-down, CTL attack induction, systemic: IT, IV; tumor-specific CTLs.

Embodiments of the invention build on phase I clinical trialsdemonstrating safety and efficacy of vaccinia virus as a cancertreatment. A metastatic melanoma clinical trial with seven patients witha median life expectancy <6 months enrolled were conducted usingintratumoral injections in a bi-weekly dose escalation study. The trialindicated that vaccinia virus was safe, well-tolerated and resulted intumor responses in 5 patients (71%) with two long-term survivorsdisease-free.

Initial results from phase I/II trials have also demonstrated continuedsafety of JX-594. Flu-like symptoms were observed for 5-8 days. Atransient decrease platlelets (plt), lymph, absolute neutrophil count(ANC) (typically Gr1-2) was also observed. There was one death on studyDay 8, but was determined not to be related to treatment. Overall,JX-594 viremia was well-tolerated with an immediate post-injection(15-30 min.): max 3×10⁸ total genomes in blood and a replication peak(Day 5-8): max 10¹⁰ total genomes in blood.

Other embodiments of the invention are discussed throughout thisapplication. Any embodiment discussed with respect to one aspect of theinvention applies to other aspects of the invention as well and viceversa. The embodiments in the Example section are understood to beembodiments of the invention that are applicable to all aspects of theinvention.

The terms “inhibiting,” “reducing,” or “prevention,” or any variation ofthese terms, when used in the claims and/or the specification includesany measurable decrease or complete inhibition to achieve a desiredresult.

The use of the word “a” or “an” when used in conjunction with the term“comprising” in the claims and/or the specification may mean “one,” butit is also consistent with the meaning of “one or more,” “at least one,”and “one or more than one.”

It is contemplated that any embodiment discussed herein can beimplemented with respect to any method or composition of the invention,and vice versa. Furthermore, compositions and kits of the invention canbe used to achieve methods of the invention.

Throughout this application, the term “about” is used to indicate that avalue includes the standard deviation of error for the device or methodbeing employed to determine the value.

The use of the term “or” in the claims is used to mean “and/or” unlessexplicitly indicated to refer to alternatives only or the alternativesare mutually exclusive, although the disclosure supports a definitionthat refers to only alternatives and “and/or.”

As used in this specification and claim(s), the words “comprising” (andany form of comprising, such as “comprise” and “comprises”), “having”(and any form of having, such as “have” and “has”), “including” (and anyform of including, such as “includes” and “include”) or “containing”(and any form of containing, such as “contains” and “contain”) areinclusive or open-ended and do not exclude additional, unrecitedelements or method steps.

Other objects, features and advantages of the present invention willbecome apparent from the following detailed description. It should beunderstood, however, that the detailed description and the specificexamples, while indicating specific embodiments of the invention, aregiven by way of illustration only, since various changes andmodifications within the spirit and scope of the invention will becomeapparent to those skilled in the art from this detailed description.

DESCRIPTION OF THE DRAWINGS

The following drawings form part of the present specification and areincluded to further demonstrate certain aspects of the presentinvention. The invention may be better understood by reference to one ormore of these drawings in combination with the detailed description ofspecific embodiments presented herein.

FIG. 1—JX-594 intravenous (IV) treatment of spontaneous rathepatocellular carcinoma (HCC). Rats received the mutagenN-Nitrosomorpholine (NMM) in their drinking water (175 mg/L) for aperiod of 8 weeks and were then followed by ultrasound (US) until HCCtumors had formed and were 300-400 mm³ (typically after 16-20 weeks).Animals then received 3 intravenous doses (one every two weeks, arrows)of either PBS (n=17) or 1×10⁸ PFU of JX-594 virus (n=6). Subsequenttumor volumes were then calculated based on tumor measurements from USimaging.

FIGS. 2A-2B—JX-594 Intravenous dose treatment of VX2 liver tumors inrabbits, efficacy against primary tumor and metastases. VX2 cells (froma dissociated 1 mm³ tumor) were implanted into the liver of New Zealandwhite rabbits and tumor growth followed by ultrasound (US) and CT scan.Once tumors reached 2-4 cm³ animals were treated with a single dose ofPBS (n=7) or JX-594 (1×10⁹ PFU), via intravenous or US guided ITinjection (n=3/group). (FIG. 2A) Subsequent tumor volume in the liverwas measured 7 weeks later by CT scan and (FIG. 2B) number of detectabletumor metastases in the lungs were counted following CT scan at weeks 6and 7.

FIG. 3—JX-594 and JX-963 lower dose intravenous repeat treatments of VX2liver tumors in rabbits. Tumor cells were implanted as described in(FIGS. 2A-2B). Animals were treated intravenously 3 times (every twoweeks, arrows) after tumors reached 2-4 cm³ with 1×10⁸ PFU of JX-594,JX-963 or vvDD (n=6/group), or PBS (n=18). Subsequent primary tumorvolume was followed by CT scan.

FIG. 4—Effects of JX-594, vvDD and JX-963 on lung metastases in rabbitsbearing VX2 liver tumors. Animals (from studies described in FIG. 3)were examined for liver metastases by CT scan at weekly intervals afterthe beginning of therapy. The mean number of detectable metastases peranimal in each group is shown.

FIG. 5—Survival of rabbits bearing VX2 liver tumors after IV delivery ofJX-963. Animals bearing liver tumors were treated with 3 doses of 1×10⁸PFU of JX-963 as described in FIG. 3. A Kaplin-Meier survival curve ofthese animals and the control treated group are shown. As the JX-594 andvvDD groups did not show significant differences in survival, JX594 andvvDD groups were not included.

FIGS. 6A-6C—Burst ratio of vaccinia strains, cytopathic effect, andsystemic delivery of viral strains to tumors. (FIG. 6A) Burst ratio ofvaccinia strains in tumor to normal cells. Different vaccinia strainswere used to infect both primary normal cells (NHBE) and a tumor cellline (A2780) at a Multiplicity of infection (MOI) of 1.0 Plaque FormingUnit (PFU)/cell. Virus collected 48 h later was titered by plaque assayand the ratio of virus produced (per cell) in tumor to normal cells isrepresented. (FIG. 6B) Cytopathic effect produced by viral infection.Western Reserve, Adenovirus serotype 5 and Adenovirus strain d/1520(ONYX-015) (in some assays) were added to cell lines at ranges of MOIs(PFU/cell), and cell viability measured after 72 hours using MTS(Promega). The MOI of virus (PFU/cell) needed to reduce the cellviability to 50% of untreated control wells (ED₅₀) is plotted. (FIG. 6C)Systemic delivery of viral strains to tumors. 1×10⁹ PFU of vacciniastrain Western Reserve or Adenovirus serotype 5 were deliveredintravenously to immunocompetent mice bearing subcutaneous CMT 64 or JCtumors. Mice were sacrificed after 48 or 72 hours andimmunohistochemistry performed against viral coat proteins on paraffinembedded sections of tumor tissue. Graphs show scoring of positive cellsin each tumour (*=none detectable). For each condition results are basedon tumours from 3 mice, and for each tumour, ten randomly chosen fieldsof view were scored.

FIG. 7—Cytopathic effect of WR and vvDD on a panel of human tumor celllines. EC₅₀ values were determined 72 h following infection of tumorcell lines with WR or vvDD. The MOI of virus (PFU/cell) needed to reducethe cell viability to 50% of untreated control wells (ED₅₀) is plotted.

FIGS. 8A-8C—Effects of overexpression of H-Ras on viral replication,biodistribution of WR and vvDD following systemic delivery to tumorbearing mice, and viral gene expression quantified by light production.(FIG. 8A) Effects of overexpression of H-Ras on viral replication. NIH3T3 cells, and NIH 3T3 cells expressing activated H-Ras, eitherproliferating or serum starved, were infected with different strains ofvaccinia at an MOI of 1.0 PFU/cell. Viral strains were parental WesternReserve (WR), and WR containing deletions or insertions in either theThymidine Kinase (TK) gene (vJS6), the viral growth factor (VGF) gene(vSC20), or containing deletions in both these genes (vvDD). Infectiousvirus was titered by plaque assay after 48 h. (FIG. 8B). Biodistributionof WR and vvDD following systemic delivery to tumor bearing mice.Athymic CD1 nu/nu mice bearing subcutaneous human HCT 116 tumors(arrowed) were treated with 1×10⁷ PFU of vaccinia strains via tail veininjection. Viral strains (WR and vvDD) expressed luciferase, and thesubsequent biodistribution of viral gene expression was detected bybioluminescence imaging in an IVIS100 system (Xenogen Corp, Alameda)following addition of the substrate luciferin at the times indicatedafter treatment. (FIG. 8C) Viral gene expression, as quantified by lightproduction, was plotted over time for the regions of interest coveringthe whole body (ventral image)(dashed line, open symbols), or from thetumor only (dorsal view)(solid line, filled symbols) for BALB/c micebearing subcutaneous JC tumors (n=5 mice/group) and treated with 1×10⁷PFU of either virus by tail vein injection.

FIGS. 9A-9C—Rabbits bearing VX2 tumors implanted into the liver werefollowed by CT imaging at times after tumor implantation, CTL assayagainst VX2 tumor cells, and Rabbits re-treated with JX-963. (FIG. 9A)Rabbits bearing VX2 tumors implanted into the liver were followed by CTimaging at times after tumor implantation. 1×10⁹ PFU of viruses vvDD andJX-963 were delivered by ear vein injection at 2, 3 and 4 weeks aftertumor implantation (arrows), when tumors measured 5 cm3. The number ofdetectable lung metastases was also measured in these animals(representative CT images of primary liver tumors are shown at 8 weeks)(n=18 for control treated animals; n=6 for vvDD treated; n=6 for JX-963treated). (FIG. 9B) CTL assay targeting VX2 tumor cells. CTL assay wasperformed by FACS analysis using pre-labeled VX2 cells mixed with 12.5×;25× and 50× unlabelled peripheral blood lymphocytes from rabbits bearingVX2 tumors and treated with JX-963; from untreated animals with VX2tumors; and from nave animals. Cell death was quantified by the ACT1assay (Cell Technology, Mountain View). (FIG. 9C) Four Rabbits treatedas in (A) with JX-963 were re-treated with 1×10⁹ PFU of JX-963 at Day 42after implantation (arrow), subsequent tumor volume was followed by CTscan.

FIGS. 10A-10B—Viral production of cell lines infected with either WR orAd5, and cytopathic effect produced by viral infection. (FIG. 10A)Different cell lines were infected with either Western Reserve orAdenovirus serotype 5 at an MOI of 1.0 PFU/cell. Amounts of virusproduced (Infectious Units/cell) 48 h later were titered by plaqueassay. (FIG. 10B) Mice treated as in FIG. 1C were sacrificed and tumorsections stained for viral coat proteins. Representative photographsshow sections at 72 h and 10 days post-treatment.

FIG. 11—Viral production of cell lines infected with either WR or Ad5.Human tumor cell lines (Panc-1 and MCF-7) or human immortalized butnon-transformed cell lines (Beas-2B and MRC-5), either proliferating orgrown to contact inhibition (N.B. tumor cells did not become contactinhibited), were treated with different strains of vaccinia at an MOI of1.0 PFU/cell. Strains used were Western Reserve (WR) and WR containingdeletions in either the Thymidine Kinase (TK) gene (vJS6), the viralgrowth factor (VGF) gene (vSC20), or containing deletions in both thesegenes (vvDD). Virus produced after 48 h was titered by plaque assay.

FIG. 12—Recovery of systemically delivered vvDD. Recovery of vvDDdelivered systemically (intraperitoneal injection of 1×10⁹ PFU) toC57B/6 mice bearing subcutaneous MC38 tumors. Mice were sacrificed ondays 5 or 8 after treatment (n=8/group) and different tissues recoveredand viral infectious units (PFU/mg tissue) titered by plaque assay(*=below the limits of detection).

FIGS. 13A-13B—Efficacy of vvDD following delivery by different routesinto tumor bearing mouse models. (FIG. 13A) Single intravenousinjections of 1×10⁹ PFU of viral strain vvDD or vaccinia Wyeth strainbearing a Thymidine Kinase deletion were delivered to immunocompetentmice bearing subcutaneous TIB 75 tumors (50-100 mm³). Tumor volume wasmeasured by calipers, (n=8/group). (FIG. 13B) 1×10⁹ PFU of vvDD wasdelivered intratumorally (IT) or intraperitoneally (IP) to either SCIDmice bearing subcutaneous HT29 tumors or C57B/6 mice bearingsubcutaneous MC38 tumors and subsequent tumor volume compared to anuninfected control group (n=8/group).

FIG. 14—Formation of neutralizing antibodies following treatment of VX2tumor bearing rabbits with JX-963 (1×10⁸ PFU). Dilutions of plasmaobtained from rabbits at indicated times were incubated with a knownnumber of viral PFU, and dilutions required to retain 50% of the plaquesare shown (n=3).

FIG. 15. Clinical trial study design for hepatic tumors using JX-594 byintratumoral injection.

FIG. 16. Clinical trial study design for melanomoa using JX-594 byintratumoral injection.

FIG. 17. Targeted oncolytic virotherapy having multiple, novelmechanisms for cancer eradication.

FIG. 18. Long-term survivors disease-free after JX-594 phase I clinicaltrial metastatic melanoma. Patient 1, top, is a 32 year-old woman:Refractory:DTIC, IL-2; injected tumors: CR; non-injectedmetastases:-dermal: CR; breast: CR with surgery. Alive, disease-free1.5+ years. Patient 2, bottom, 75 year-old man: multiple metastaticsites (n=24); injected tumors: CR; non-injected metastases:-CR; Alive,disease-free 3+ years.

FIG. 19. JX-594 phase I clinical trial responses in both injected andnon-injected tumors.

FIG. 20. JX594-IT-hep001—patient demographics and treatmentstatus—cohort 1 and 2.

FIG. 21. JX594-IT-hep001—patient demographics and treatmentstatus—cohort 3.

FIG. 22. Intravenous dissemination of JX-594 in bloodstream: early leakfrom tumor corresponds with dose, mostly cleared by 6 hrs.

FIG. 23. Replication viremia of JX-594 evident in 80% of patients:Secondary wave of JX-594 in blood demonstrated in cycles 1-7. (+) afterinput dose cleared, (−) Level below limit detection, squares=patientoff-study, and (p)=data pending. Limit of detection=700 genomes/ml.

FIG. 24. Replication viremia of JX-594 evident in 80% of patients:Secondary wave of JX-594 in blood cycles 1-7, days 3-22.

FIG. 25. JX-594 replication-associated vascular shutdown acutetreatment-induced avascular necrosis (pt. 1, gastric cancer).

FIG. 26. Long-term Stable Disease with JX-594 squamous cell carcinomacontrol (lung-cohort 2).

FIG. 27. Metabolic (PET) response JX-594 injected tumor melanomaresponse after 2 cycles of JX-594(cohort 3).

FIG. 28. Metabolic (PET) response JX-594 injected tumor liver carcinomalong-term control (cohort 2) for 9+ months.

FIG. 29. Tumor Marker Response: 99.9% decrease in AFP Rapid liver cancerdestruction demonstrated by blood marker.

FIG. 30. Body Weight Gain on JX-594 10% increase (6 kg; 14 lb.)demonstrates tolerability, efficacy.

FIG. 31. Systemic viremia and tumor response: JX-594-associated viremia,resultant systemic efficacy (HCC-cohort 2)—AFP decrease 40%.

FIG. 32. Systemic JX-594 delivery to tumors and response: Efficacy innon-injected distant tumors after liver met injection. PET metabolicresponse in two non-injected tumors after 2 cycles (Pt. 304, cohort 3).

FIG. 33. Treatment, Efficacy and Survival Data: Tumor responses by CTand PET, long-term survivors.

FIG. 34. Trial profile.

FIGS. 35A-35B. Key hematologic tests and liver function tests (errorbars, standard error of mean). (FIG. 35A) Increase in ANC correlateswith increased JX-594 dose and expression of hGM-CSF. Filled bars: ANC;open bars: GM-CSF. X-axis: patient identification number. (FIG. 35B) ALTlevels of patients in cohorts 3 and 4 in the first cycle. The majorityof patients experienced no significant changes in ALT levels over time;mild, transient transaminitis was also observed.

FIGS. 36A-36C. Changes in hematologic tests. (FIG. 36A) Dose-dependentthrombocytopenia. (FIG. 36B) Magnitude of thrombocytopenia iscycle-independent. (FIG. 36C) Magnitude of changes of in ANC,eosinophils, and monocytes were more significant in cycle 1 compared tosubsequent cycles. White bars: ANC; grey bars: eosinophils; black bars:monocytes. Error bars represent standard error of the mean.

FIGS. 37A-37F. Pharmacokinetics, blood-borne spread and distant tumorinfection by JX-594. (FIG. 37A) Acute genome concentrations incirculation. JX-594 genomes were detected as early as 15 minutespost-injection. For cohorts 1 to 3, the acute clearance rates wereconsistent between cohorts. (FIG. 37B) JX-594 genome concentrations ofcohorts 1 and 3 in cycle 1 are shown. Concentrations of JX-594 genomes,including levels of secondary viremia peaks, were dose-related. LOQ:limit of quantitation. Error bars represent standard error of the mean.(FIG. 37C) Representative JX-594 genome concentrations in cycle 1. (FIG.37D) JX-594 recovery and hGM-CSF expression from a melanoma patient(cohort 3). High levels of JX-594 genomes and GM-CSF were detected incirculation as well as malignant body fluids (cohort 3, melanomapatient). Asterisk: undetectable; PE: pleural effusion. (FIG. 37E)Infectious JX-594 presence was demonstrated by lac-Z expression (blue)from cells in a malignant pleural effusion. (FIG. 37F) Biopsy samplefrom non-injected liver cancer metastasis (neck) showing vaccinia virusB5R staining (arrows; brown).

FIGS. 38A-38B. Antitumoral efficacy. (FIG. 38A) Representative CT scansand tumor measurements of a non-small cell lung cancer target tumor.circles: tumors. Arrow: time when JX-594 administration was initiated.Note the changes in the cross sectional area of the tumor over time.(FIG. 38B) Representative physical, CT and PET-CT scan resultsdemonstrating objective tumor response (after 4 cycles) of metastatictumor in neck, injected after induction of high titer neutralizingantibodies to JX-594.

DETAILED DESCRIPTION OF THE INVENTION

The present invention concerns the use of oncolytic poxviruses for thetreatment of cancer. In particular, the use of a vaccinia virusexpressing GM-CSF to achieve a particular degree of oncolysis isdescribed. In another embodiment, a GM-CSF-expressing poxvirus can beengineered to be more effective or more efficient at killing cancercells and/or be less toxic or damaging to non-cancer cells, by mutationor modification of gene products such that the alterations render theviruses better able to infect the host, less toxic to host cells, and/orbetter able to infect cancer cells. A particular modification is torender the virus deficient in thymidine kinase (TK) function.

The present invention also concerns the intravenous administration ofGM-CSF-expressing poxviruses to treat both primary tumors and distantmetastases. The inventors have demonstrated that two differentGM-CSF-expressing poxviruses were well-tolerated intravenously andhighly effective against disseminated tumors and metastases. Inaddition, a GM-CSF-expressing poxvirus had significantly better efficacyagainst both primary tumors and lung metastases than itsnon-GM-CSF-expressing control after intravenous administration. Also,this virus had significantly better efficacy against both primary tumorsand lung metastases than a comparable virus (Wyeth vaccine strain)despite an additional deletion in the vgf gene not present in the othervirus. Therefore, intravenous administration with a vaccinia expressinghuman GM-CSF resulted in significantly better efficacy over the samevaccinia without GM-CSF, and intravascular administration of a WR straindeletion mutant expressing human GM-CSF was significantly better than astandard vaccine strain expressing GM-CSF. These viruses werewell-tolerated after intravenous administration to both tumor-bearing(rats and rabbits) and normal animals (rabbits). Treated animals did notlose weigh while tumor-bearing animals that did not receive treatmentlost weight. Survival was increased following intravenous treatment. Nosignificant organ toxicity was noted by blood testing or histopathology.The only reproducible histopathological findings were multiple sites oflymphoid hyperplasia that were noted following treatment (consistentwith systemic immunostimulation). No significant toxicities were notedon histopathology. Therefore, these GM-CSF expressing poxviruses arewell-tolerated at doses that were highly effective against systemiccancer.

I. Poxviruses

Poxviruses have been known for centuries, with the characteristic pockmarks produced by variola virus (smallpox) giving this family its name.It appears that smallpox first emerged in China and the Far East over2000 years ago. Fortunately, this often fatal virus has now beeneradicated, with the last natural outbreak occurring in 1977 in Somalia.

The poxvirus viral particle is oval or brick-shaped, measuring some200-400 nm long. The external surface is ridged in parallel rows,sometimes arranged helically. The particles are extremely complex,containing over 100 distinct proteins. The extracellular forms containtwo membranes (EEV—extracellular enveloped virions), whereasintracellular particles only have an inner membrane (IMV—intracellularmature virions). The outer surface is composed of lipid and protein thatsurrounds the core, which is composed of a tightly compressednucleoprotein. Antigenically, poxviruses are also very complex, inducingboth specific and cross-reacting antibodies. There are at least tenenzymes present in the particle, mostly concerned with nucleic acidmetabolism/genome replication.

The genome of the poxvirus is linear double-stranded DNA of 130-300 Kbp.The ends of the genome have a terminal hairpin loop with several tandemrepeat sequences. Several poxvirus genomes have been sequenced, withmost of the essential genes being located in the central part of thegenome, while non-essential genes are located at the ends. There areabout 250 genes in the poxvirus genome.

Replication takes place in the cytoplasm, as the virus is sufficientlycomplex to have acquired all the functions necessary for genomereplication. There is some contribution by the cell, but the nature ofthis contribution is not clear. However, even though poxvirus geneexpression and genome replication occur in enucleated cells, maturationis blocked, indicating some role by the cell.

The receptors for poxviruses are not generally known, but probably aremultiple in number and on different cell types. For vaccinia, one of thelikely receptors is EGF receptor (McFadden, 2005). Penetration may alsoinvolve more than one mechanism. Uncoating occurs in two stages: (a)removal of the outer membrane as the particle enters the cell and in thecytoplasm, and (b) the particle is further uncoated and the core passesinto the cytoplasm.

Once into the cell cytoplasm, gene expression is carried out by viralenzymes associated with the core. Expression is divided into 2 phases:early genes: which represent about of 50% genome, and are expressedbefore genome replication, and late genes, which are expressed aftergenome replication. The temporal control of expression is provided bythe late promoters, which are dependent on DNA replication for activity.Genome replication is believed to involve self-priming, leading to theformation of high molecular weight concatemers, which are subsequentlycleaved and repaired to make virus genomes. Viral assembly occurs in thecytoskeleton and probably involves interactions with the cytoskeletalproteins (e.g., actin-binding proteins). Inclusions form in thecytoplasm that mature into virus particles. Cell to cell spread mayprovide an alternative mechanism for spread of infection. Overall,replication of this large, complex virus is rather quick, taking just 12hours on average.

At least nine different poxviruses cause disease in humans, but variolavirus and vaccinia are the best known. Variola strains are divided intovariola major (25-30% fatalities) and variola minor (same symptoms butless than 1% death rate). Infection with both viruses occurs naturallyby the respiratory route and is systemic, producing a variety ofsymptoms, but most notably with variola characteristic pustules andscarring of the skin.

A. Vaccinia Virus

Vaccinia virus is a large, complex enveloped virus having a lineardouble-stranded DNA genome of about190Khttp://www.answers.com/topic/base-pair by and encoding forapproximately 250 genes. Vaccinia is well-known for its role as avaccine that eradicated smallpox. Post-eradication of smallpox,scientists have been exploring the use of vaccinia as a tool fordelivering genes into biological tissues (gene therapy and geneticengineering). Vaccinia virus is unique among DNA viruses as itreplicates only in the cytoplasm of the host cell. Therefore, the largegenome is required to code for various enzymes and proteins needed forviral DNA replication. During replication, vaccinia produces severalinfectious forms which differ in their outer membranes: theintracellular mature virion (IMV), the intracellular enveloped virion(IEV), the cell-associated enveloped virion (CEV) and the extracellularenveloped virion (EEV). IMV is the most abundant infectious form and isthought to be responsible for spread between hosts. On the other hand,the CEV is believed to play a role in cell-to-cell spread and the EEV isthought to be important for long range dissemination within the hostorganism.

Vaccinia encodes several proteins giving the virus resistance tointerferons. K3L is a protein having homology with eIF-2a. K3L proteininhibits the action of PKR, an activator of interferons. E3L is anothervaccinia protein that also inhibits PKR activation and is also able tobind double-stranded RNA.

Vaccinia virus is closely related to the virus that causes cowpox. Theprecise origin of vaccinia is unknown, but the most common view is thatvaccinia virus, cowpox virus, and variola virus (the causative agent forsmallpox) were all derived from a common ancestral virus. There is alsospeculation that vaccinia virus was originally isolated from horses. Avaccinia virus infection is mild and typically asymptomatic in healthyindividuals, but it may cause a mild rash and fever, with an extremelylow rate of fatality. An immune response generated against a vacciniavirus infection protects that person against a lethal smallpoxinfection. For this reason, vaccinia virus was used as a live-virusvaccine against smallpox. The vaccinia virus vaccine is safe because itdoes not contain the smallpox virus, but occasionally certaincomplications and/or vaccine adverse effects may arise, especially ifthe vaccine is immunocompromised.

As discussed above, vaccinia viruses have been engineered to express anumber of foreign proteins. One such protein is granulocyte-macrophagecolony stimulating factor, or GM-CSF. GM-CSF is a protein secreted bymacrophages that stimulates stem cells to produce granulocytes(neutrophils, eosinophils, and basophils) and macrophages. Human GM-CSFis glycosylated at amino acid residues 23 (leucine), 27 (asparagine),and 39 (glutamic acid) (see U.S. Pat. No. 5,073,627, incorporated byreference). GM-CSF is also known as molgramostim or, when the protein isexpressed in yeast cells, sargramostim (trademarked Leukine®), which isused as a medication to stimulate the production of white blood cells,especially granulocytes and macrophages, following chemotherapy. Avaccinia virus expressing GM-CSF has previously been reported. However,it was delivered not as an oncolytic agent, but merely as a deliveryvector for GM-CSF. As such, it has been administered to patients atdosage below that which can achieve significant oncolysis. Herein isdescribed the use of a GM-CSF expressing vaccinia virus that, in someembodiments, is administered at concentrations greater than 1×10⁸ pfu orparticles.

B. Modified Poxviruses

Viruses are frequently inactivated, inhibited, or cleared byimmunomodulatory molecules such as interferons (-α, -β, -γ) and tumornecrosis factor-α (TNFα) (Moss, 1996). Host tissues andinflammatory/immune cells frequently secrete these molecules in responseto viral infection. These molecules can have direct antiviral effectsand/or indirect effects through recruitment and/or activation ofinflammatory cells and lymphocytes. Given the importance of theseimmunologic clearance mechanisms, viruses have evolved to express geneproducts that inhibit the induction and/or function of thesecytokines/chemokines and interferons. For example, vaccinia virus (VV,and some other poxviruses) encodes the secreted protein vCKBP (B29R)that binds and inhibits the CC chemokines (e.g., RANTES, eotaxin,MIP-1-alpha) (Alcami et al., 1998). Some VV strains also express asecreted viral protein that binds and inactivates TNF (e.g., ListerA53R) (Alcami et al., 1999). Most poxvirus strains have genes encodingsecreted proteins that bind and inhibit the function of interferons-α/β(e.g., B18R) or interferon (B8R). vC12L is an IL-18-binding protein thatprevents IL-18 from inducing IFN-γ and NK cell/cytotoxic T-cellactivation.

Most poxvirus virulence research has been performed in mice. Many, butnot all, of these proteins are active in mice (B18R, for example, isnot). In situations in which these proteins are active against the mouseversions of the target cytokine, deletion of these genes leads toreduced virulence and increased safety with VV mutants with deletions ofor functional mutations in these genes. In addition, theinflammatory/immune response to and viral clearance of these mutants isoften increased compared to the parental virus strain that expresses theinhibitory protein. For example, deletion of the T1/35 kDa family ofpoxvirus-secreted proteins (chemokine-binding/-inhibitory proteins) canlead to a marked increase in leukocyte infiltration into virus-infectedtissues (Graham et al., 1997). Deletion of the vC12L gene in VV leads toreduced viral titers/toxicity following intranasal administration inmice; in addition, NK cell and cytotoxic T-lymphocyte activity isincreased together with IFN-γ induction (Smith et al., 2000). Deletionof the Myxoma virus T7 gene (able to bind IFN-γ and a broad range ofchemokines) results in reduced virulence and significantly increasedtissue inflammation/infiltration in a toxicity model (Upton et al.,1992; Mossman et al., 1996). Deletion of the M-T2 gene from myxoma virusalso resulted in reduced virulence in a rabbit model (Upton et al.1991). Deletion of the B18R anti-interferon-α/-β gene product also leadsto enhanced viral sensitivity to IFN-mediated clearance, reduced titersin normal tissues and reduced virulence (Symons et al., 1995; Colamoniciet al., 1995; Alcami et al., 2000). In summary, these viral geneproducts function to decrease the antiviral immune response andinflammatory cell infiltration into virus-infected tissues. Loss ofprotein function through deletion/mutation leads to decreased virulenceand/or increased proinflammatory properties of the virus within hosttissues.

Cytokines and chemokines can have potent antitumoral effects (Vicari etal., 2002; Homey et al., 2002). These effects can be on tumor cellsthemselves directly (e.g., TNF) or they can be indirect through effectson non-cancerous cells. An example of the latter is TNF, which can haveantitumoral effects by causing toxicity to tumor-associated bloodvessels; this leads to a loss of blood flow to the tumor followed bytumor necrosis. In addition, chemokines can act to recruit (and in somecases activate) immune effector cells such as neutrophils, eosinophils,macrophages and/or lymphocytes. These immune effector cells can causetumor destruction by a number of mechanisms. These mechanisms includethe expression of antitumoral cytokines (e.g., TNF), expression offas-ligand, expression of perforin and granzyme, recruitment of naturalkiller cells, etc. The inflammatory response can eventually lead to theinduction of systemic tumor-specific immunity. Finally, many of thesecytokines (e.g., TNF) or chemokines can act synergistically withchemotherapy or radiation therapy to destroy tumors.

Clinically effective systemic administration of recombinant versions ofthese immunostimulatory proteins is not feasible due to (1) induction ofsevere toxicity with systemic administration and (2) local expressionwithin tumor tissue is needed to stimulate local infiltration andantitumoral effects. Approaches are needed to achieve high localconcentrations of these molecules within tumor masses while minimizinglevels in the systemic circulation. Viruses can be engineered to expresscytokine or chemokine genes in an attempt to enhance their efficacy.Expression of these genes from replication-selective vectors haspotential advantages over expression from non-replicating vectors.Expression from replicating viruses can result in higher localconcentrations within tumor masses; in addition, replicating viruses canhelp to induce antitumoral immunity through tumor celldestruction/oncolysis and release of tumor antigens in a proinflammatoryenvironment. However, there are several limitations to this approach.Serious safety concerns arise from the potential for release into theenvironment of a replication-competent virus (albeit tumor-selective)with a gene that can be toxic if expressed in high local concentrations.Viruses that express potent pro-inflammatory genes from their genome maytherefore pose safety risks to the treated patient and to the generalpublic. Even with tumor-targeting, replication-selective virusesexpressing these genes, gene expression can occur in normal tissuesresulting in toxicity. In addition, size limitations prevent expressionof multiple and/or large genes from viruses such as adenovirus; thesemolecules will definitely act more efficaciously in combination.Finally, many of the oncolytic viruses in use express anti-inflammatoryproteins and therefore these viruses will counteract the induction of aproinflammatory milieu within the infected tumor mass. The result willbe to inhibit induction of antitumoral immunity, antivascular effectsand chemotherapy-/radiotherapy-sensitization.

C. Modified Vaccinia Virus

1. Interferon-Modulating Polypeptides

Interferon-α/-β blocks viral replication through several mechanisms.Interferon-γ has weaker direct viral inhibitory effects but is a potentinducer of cell-mediated immunity through several mechanisms. Viruseshave evolved to express secreted gene products that are able tocounteract the antiviral effects of interferons. For example, vacciniavirus (and other poxviruses) encodes the secreted proteins B8R and B18Rwhich bind interferon-γ and -α/-β, respectively (Smith et al., 1997;Symons et al., 1995; Alcami et al., 2000). An additional example of avaccinia gene product that reduces interferon induction is the caspase-1inhibitor B13R which inhibits activation of the interferon-γ-inducingfactor IL-18. Interferon modulating polypeptides include, but are notlimited to, B18R, which may be termed B19R in other viral strains, suchas the Copenhagen strain of vaccinia virus; B8R; B13R; vC12L; A53R; E3Land other viral polypeptides with similar activities or properties. IFNmodulating polypeptides may be divided into the non-exclusive categoriesof those that preferentially modulate IFNα and/or β pathways (such asB18R, B8R, B13R, or vC12L) and those that modulate IFNγ pathways (forexample B8R, B13R, or vC12L).

Cancer cells are frequently resistant to the effects of interferons. Anumber of mechanisms are involved. These include the fact that rassignal transduction pathway activation (e.g., by ras mutation, upstreamgrowth factor receptor overexpression/mutation, etc.), a common featureof cancer cells, leads to PKR inhibition. In addition, lymphocytes areoften inhibited in tumor masses by a variety of mechanisms includingIL-10 production and fas-L expression by tumor cells. Since lymphocytesare a major source of interferon-γ production, lymphocyte inhibitionleads to a decrease in interferon-γ production in tumors. Therefore,tumor masses tend to be sanctuaries from the effects of interferons. Inaddition, interferons themselves can have antitumoral effects. Forexample, IFN-γ can increase MHC class-I-associated antigen presentation;this will allow more efficient CTL-mediated killing of tumor cells.IFN-α/β, for example, can block angiogenesis within tumor masses andthereby block tumor growth.

2. Complement Control Polypeptides

A major mechanism for the clearance of viral pathogens is the killing ofinfected cells within the host or of virions within an organism bycomplement-dependent mechanisms. As the infected cell dies it is unableto continue to produce infectious virus. In addition, during apoptosisintracellular enzymes are released which degrade DNA. These enzymes canlead to viral DNA degradation and virus inactivation. Apoptosis can beinduced by numerous mechanisms including the binding of activatedcomplement and the complement membrane attack complex. Poxviruses suchas vaccinia have evolved to express gene products that are able tocounteract the complement-mediated clearance of virus and/orvirus-infected cells. These genes thereby prevent apoptosis and inhibitviral clearance by complement-dependent mechanisms, thus allowing theviral infection to proceed and viral virulence to be increased. Forexample, vaccinia virus complement control proteins (VCP; e.g., C21L)have roles in the prevention of complement-mediated cell killing and/orvirus inactivation (Isaacs et al., 1992). VCP also has anti-inflammatoryeffects since its expression decreases leukocyte infiltration intovirally-infected tissues. Complement control polypeptides include, butare not limited to, VCP, also known as C3L or C21L.

Cancer cells frequently overexpress cellular anti-complement proteins;this allows cancer cells to survive complement attack. Therefore, agentsthat preferentially target tumor cells due to their inherent resistanceto complement-mediated killing would have selectivity and potentialefficacy in a wide range of human cancers (Durrant et al., 2001). Inaddition, one of the hallmarks of cancer cells is a loss of normalapoptotic mechanisms (Gross et al., 1999). Resistance to apoptosispromotes carcinogenesis as well as resistance to antitumoral agentsincluding immunologic, chemotherapeutic and radiotherapeutic agents(Eliopoulos et al., 1995). Apoptosis inhibition can be mediated by aloss of pro-apoptotic molecule function (e.g., bax), an increase in thelevels/function of anti-apoptotic molecules (e.g., bcl-2) and finally aloss of complement sensitivity.

3. TNF-Modulating Polypeptides

One of the various mechanisms for the clearance of viral pathogens isthe killing of infected cells within the host by the induction ofapoptosis, as described above. Apoptosis can be induced by numerousmechanisms including the binding of TNF and lymphotoxin-alpha (LTα) tocellular TNF receptors, which triggers intracellular signaling cascades.Activation of the TNF receptors function in the regulation of immune andinflammatory responses, as well as inducing apoptotic cell death(Wallach et al., 1999)

Various strains of poxviruses, including some vaccinia virus strains,have evolved to express gene products that are able to counteract theTNF-mediated clearance of virus and/or virus-infected cells. Theproteins encoded by these genes circumvent the proinflammatory andapoptosis inducing activities of TNF by binding and sequesteringextracellular TNF, resulting in the inhibition of viral clearance.Because viruses are not cleared, the viral infection is allowed toproceed, and thus, viral virulence is increased. Various members of thepoxvirus family express secreted viral TNF receptors (vTNFR). Forexample, several poxviruses encode vTNFRs, such as myxoma (T2 protein),cowpox and vaccinia virus strains, such as Lister, may encode one ormore of the CrmB, CrmC (A53R), CrmD, CrmE, B28R proteins and/orequivalents thereof. These vTNFRs have roles in the prevention ofTNF-mediated cell killing and/or virus inactivation (Saraiva and Alcami,2001). TNF modulatory polypeptides include, but are not limited to,A53R, B28R (this protein is present, but may be inactive in theCopenhagen strain of vaccinia virus) and other polypeptides with similaractivities or properties.

One of the hallmarks of cancer cells is aberrant gene expression, whichmay lead to a loss of sensitivity to a number of molecular mechanismsfor growth modulation, such as sensitivity to the anti-cancer activitiesof TNF. Thus, viral immunomodulatory mechanisms may not be required forthe propagation of a virus within the tumor microenvironment.

4. Serine Protease Inhibitors

A major mechanism for the clearance of viral pathogens is the inductionof apoptosis in infected cells within the host. As the infected celldies it is unable to continue to produce infectious virus. In addition,during apoptosis intracellular enzymes are released which degrade DNA.These enzymes can lead to viral DNA degradation and virus inactivation.Apoptosis can be induced by numerous mechanisms including the binding ofcytokines (e.g., tumor necrosis factor), granzyme production bycytotoxic T-lymphocytes or fas-ligand binding; caspase activation is acritical part of the final common apoptosis pathway. Viruses haveevolved to express gene products that are able to counteract theintracellular signaling cascade induced by such molecules includingfas-ligand or tumor necrosis factor (TNF)/TNF-related molecules (e.g.,E3 10.4/14.5, 14.7 genes of adenovirus (Wold et al., 1994); E1B-19 kD ofadenovirus (Boyd et al., 1994); crmA from cowpoxvirus; B13R fromvaccinia virus) (Dobbelstein et al., 1996; Kettle et al., 1997)). Thesegene products prevent apoptosis by apoptosis-inducing molecules and thusallow viral replication to proceed despite the presence of antiviralapoptosis-inducing cytokines, fas, granzyme or other stimulators ofapoptosis.

VV SPI-2/B13R is highly homologous to cowpox CrmA; SPI-1 (VV) is weaklyhomologous to CrmA (Dobbelstein et al., 1996). These proteins areserpins (serine protease inhibitors) and both CrmA and SPI-2 have rolesin the prevention of various forms of apoptosis. Inhibition ofinterleukin-1β-converting enzyme (ICE) and granzyme, for example, canprevent apoptosis of the infected cell. These gene products also haveanti-inflammatory effects. They are able to inhibit the activation ofIL-18 which in turn would decrease IL-18-mediated induction of IFN-γ.The immunostimulatory effects of IFN-γ on cell-mediated immunity arethereby inhibited (Kettle et al., 1997). SPIs include, but are notlimited to, B13R, B22R, and other polypeptides with similar activitiesor properties.

One of the hallmarks of cancer cells is a loss of normal apoptoticmechanisms (Gross et al., 1999). Resistance to apoptosis promotescarcinogenesis as well as resistance to antitumoral agents includingimmunologic, chemotherapeutic and radiotherapeutic agents (Eliopoulos etal., 1995). Apoptosis inhibition can be mediated by a loss ofpro-apoptotic molecule function (e.g., bax) or an increase in thelevels/function of anti-apoptotic molecules (e.g., bcl-2).

5. IL-1β-Modulating Polypeptides

IL-1β is a biologically active factors that acts locally and alsosystemically. Only a few functional differences between IL-1β and IL-1αhave been described. The numerous biological activities of IL-1β isexemplified by the many different acronyms under which IL-1 has beendescribed. IL-1 does not show species specificity with the exception ofhuman IL-1β that is inactive in porcine cells. Some of the biologicalactivities of IL-1 are mediated indirectly by the induction of thesynthesis of other mediators including ACTH (Corticotropin), PGE2(prostaglandin E2), PF4 (platelet factor4), CSF (colony stimulatingfactors), IL-6, and IL-8. The synthesis of IL-1 may be induced by othercytokines including TNF-α, IFN-α, IFN-β and IFN-γ and also by bacterialendotoxins, viruses, mitogens, and antigens. The main biologicalactivity of IL-1 is the stimulation of T-helper cells, which are inducedto secrete IL-2 and to express IL-2 receptors. Virus-infectedmacrophages produce large amounts of an IL-1 inhibitor that may supportopportunistic infections and transformation of cells in patients withT-cell maturation defects. IL-1 acts directly on B-cells, promotingtheir proliferation and the synthesis of immunoglobulins. IL-1 alsofunctions as one of the priming factors that makes B-cells responsive toIL-5. IL-1 stimulates the proliferation and activation of NK-cells andfibroblasts, thymocytes, glioblastoma cells.

Blockade of the synthesis of IL-1β by the viral protein is regarded as aviral strategy allowing systemic antiviral reactions elicited by IL-1 tobe suppressed or diminished. Binding proteins effectively blocking thefunctions of IL-1 with similar activity as B1 5R have been found also tobe encoded by genes of the cowpox virus. Vaccinia virus also encodesanother protein, designated B8R, which behaves like a receptor forcytokines (Alcami and Smith, 1992; Spriggs et al., 1992). IL-1modulating polypeptides include, but are not limited to, B13R, B15R, andother polypeptides with similar activities or properties.

One of the hallmarks of cancer cells is aberrant gene expression, whichmay lead to a loss of sensitivity to a number of molecular mechanismsfor growth modulation, such as sensitivity to the anti-cancer activitiesof IL-1. Thus, viral immunomodulatory mechanisms may not be required forthe propagation of a virus within the tumor microenvironment.

6. EEV Form

Viral spread to metastatic tumor sites, and even spread within aninfected solid tumor mass, is generally inefficient (Heise et aL, 1999).Intravenous administration typically results in viral clearance orinactivation by antibodies (e.g., adenovirus) (Kay et al., 1997) and/orthe complement system (e.g., HSV) (Ikeda et al., 1999). In addition tothese immune-mediated mechanisms, the biodistribution of these virusesresults in the vast majority of intravenous virus depositing withinnormal tissues rather than in tumor masses. Intravenous adenovirus, forexample, primarily ends up within the liver and spleen; less than 0.1%of the input virus depositing within tumors, even in immunodeficientmice (Heise et al., 1999). Therefore, although some modest antitumoralefficacy can be demonstrated with extremely high relative doses inimmunodeficient mouse tumor models, intravenous delivery is extremelyinefficient and significantly limits efficacy.

Vaccinia virus has the ability to replicate within solid tumors andcause necrosis. In addition, thymidine kinase-deletion mutants caninfect tumor masses and ovarian tissue and express marker genespreferentially in mouse tumor model systems (Gnant et al., 1999).However, since these studies generally determined tumor targeting basedon marker gene expression after 5 days, it is unclear whether the viruspreferentially deposits in, expresses genes in or replicates intumor/ovary tissue (Puhlmann et al., 2000). Regardless of the mechanism,the anti-tumoral efficacy of this virus without additional transgeneswas not statistically significant (Gnant et al., 1999). In contrast,intratumoral virus injection had significant anti-tumoral efficacy(McCart et al. 2000). Therefore, i.v. efficacy could be improved if i.v.delivery to the tumor were to be improved.

Vaccinia virus replicates in cells and produces both intracellular virus(IMV, intracellular mature virus; IEV, intracellular enveloped virus)and extracellular virus (REV, extracellular enveloped virus; CEV,cell-associated extracellular virus) (Smith et al., 1998). IMVrepresents approximately 99% of virus yield following replication bywild-type vaccinia virus strains. This virus form is relatively stablein the environment, and therefore it is primarily responsible for spreadbetween individuals; in contrast, this virus does not spread efficientlywithin the infected host due to inefficient release from cells andsensitivity to complement and/or antibody neutralization. In contrast,EEV is released into the extracellular milieu and typically representsonly approximately 1% of the viral yield (Smith et al., 1998). EEV isresponsible for viral spread within the infected host and is relativelyeasily degraded outside of the host. Importantly, EEV has developedseveral mechanisms to inhibit its neutralization within the bloodstream.First, EEV is relatively resistant to complement (Vanderplasschen etal., 1998); this feature is due to the incorporation of host cellinhibitors of complement into its outer membrane coat plus secretion ofVaccinia virus complement control protein (VCP) into local extracellularenvironment. Second, EEV is relatively resistant to neutralizingantibody effects compared to IMV (Smith et al., 1997). EEV is alsoreleased at earlier time points following infection (e.g., 4-6 hours)than is IMV (which is only released during/after cell death), andtherefore spread of the EEV form is faster (Blasco et al., 1993).

Unfortunately, however, wild-type vaccinia strains make only very smallamounts of EEV, relatively. In addition, treatment with vaccinia virus(i.e., the input dose of virus) has been limited to intracellular virusforms to date. Standard vaccinia virus (VV) manufacturing andpurification procedures lead to EEV inactivation (Smith et al., 1998),and non-human cell lines are frequently used to manufacture the virus;EEV from non-human cells will not be protected from complement-mediatedclearance (complement inhibitory proteins acquired from the cell by EEVhave species restricted effects). Vaccinia virus efficacy has thereforebeen limited by the relative sensitivity of the IMV form toneutralization and by its inefficient spread within solid tumor masses;this spread is typically from cell to adjacent cell. IMV spread todistant tumor masses, either through the bloodstream or lymphatics, isalso inefficient.

Therefore, the rare EEV form of vaccinia virus has naturally acquiredfeatures that make it superior to the vaccinia virus form used inpatients to date (IMV); EEV is optimized for rapid and efficient spreadthrough solid tumors locally and to regional or distant tumor sites.Since EEV is relatively resistant to complement effects, when it isgrown in a cell type from the same species, this virus form will haveenhanced stability and retain activity longer in the blood followingintravascular administration than standard preparations of vacciniavirus (which contain exclusively IMV) (Smith et al., 1998). Since EEV isresistant to antibody-mediated neutralization, this virus form willretain activity longer in the blood following intravascularadministration than standard preparations of vaccinia virus (whichcontain almost exclusively IMV) (Vanderplasschen et al., 1998). Thisfeature will be particularly important for repeat administration onceneutralizing antibody levels have increased; all approved anti-cancertherapies require repeat administration. Therefore, the EEV form ofvaccinia, and other poxviruses, will result in superior delivery oftherapeutic viruses and their genetic payload to tumors through thebloodstream. This will lead to enhanced systemic efficacy compared withstandard poxvirus preparations. Finally, the risk of transmission toindividuals in the general public should be reduced significantly sinceEEV is extremely unstable outside of the body. Polypeptides involved inthe modulation of the EEV form of a virus include, but are not limitedto, A34R, B5R, and various other proteins that influence the productionof the EEV form of the poxviruses. A mutation at codon 151 of A34R froma lysine to a aspartic acid (K151D mutation) renders the A34R proteinless able to tether the EEV form to the cell membrane. B5R is anEEV-membrane bound polypeptide that may bind complement. The totaldeletion of A43R may lead to increased EEV release, but markedly reducedinfectivity of the viruses, while the K151D mutation increases EEVrelease while maintaining infectivity of the released viruses. B5R hassequence homology to VCP (anti-complement), but complement inhibitionhas not yet been proven.

Briefly, one method for identifying a fortified EEV form is as follows.EEV are diluted in ice-cold MEM and mixed (1:1 volume) with active orheat-inactivated (56° C., 30 min, control) serum diluted in ice-cold MEM(final dilution of serum 1/10, 1/20, or 1/30). After incubation or 75min at 7° C., samples are cooled on ice and mAb 5B4/2F2 is added tofresh EEV samples to neutralize any contaminates (IMV and ruptured EEV).Virions are then bound to RK13 cells for one hour on ice, complement andunbound virions are washed away, and the number of plaques are countedtwo days later. The higher the plaque number the greater the resistanceto complement (Vanderplasschen et al., 1998, herein incorporated byreference). Exemplary methods describing the isolation of EEV forms ofvaccinia virus can be found in Blasco et al., 1992 (incorporated hereinby reference).

7. Other Polypeptides

Other viral immunomodulatory polypeptides may include polypeptides thatbind other mediators of the immune response and/or modulate molecularpathways associated with the immune response. For example, chemokinebinding polypeptides such as B29R (this protein is present, but may beinactive in the Copenhagen strain of vaccinia virus), C23L, vCKBP, A41Land polypeptides with similar activities or properties. Other vacciniavirus proteins such as the vaccinia virus growth factor (e.g., C11L),which is a viral EGF-like growth factor, may also be the target foralteration in some embodiments of the invention.

Other polypeptides that may be classified as viral immunomodulatoryfactors include, but are not limited to B7R, N1L, or other polypeptidesthat whose activities or properties increase the virulence of apoxvirus.

8. Vaccinia Virus-Induced Cell Fusion

In certain embodiments of the invention an alteration, deletion, ormutation of A56R or K2L encoding nucleic genes may lead to cell-cellfusion or syncyia formation induced by VV infection. Vacciniavirus-induced cell fusion will typically increase antitumoral efficacyof VV due to intratumoral viral spread. Intratumoral viral spreading bycell fusion will typically allow the virus to avoid neutralizingantibodies and immune responses. Killing and infection of adjacentuninfected cells (i.e., a “bystander effect) may be more efficient in VVwith mutations in one or both of these genes, which may result inimproved local antitumoral effects.

D. Other Poxviruses

Vaccinia virus is a member of the family Poxviridae, the subfamilyChordopoxvirinae and the genus Orthopoxvirus. The genus Orthopoxvirus isrelatively more homogeneous than other members of the Chordopoxvirinaesubfamily and includes 11 distinct but closely related species, whichincludes vaccinia virus, variola virus (causative agent of smallpox),cowpox virus, buffalopox virus, monkeypox virus, mousepox virus andhorsepox virus species as well as others (see Moss, 1996). Certainembodiments of the invention, as described herein, may be extended toother members of Orthopoxvirus genus as well as the Parapoxvirus,Avipoxvirus, Capripoxvirus, Leporipoxvirus, Suipoxvirus,Molluscipoxvirus, and Yatapoxvirus genus. A genus of poxvirus family isgenerally defined by serological means including neutralization andcross-reactivity in laboratory animals. Various members of theOrthopoxvirus genus, as well as other members of the Chordovirinaesubfamily utilize immunomodulatory molecules, examples of which areprovided herein, to counteract the immune responses of a host organism.Thus, the invention described herein is not limited to vaccinia virus,but may be applicable to a number of viruses.

E. Virus Propagation

Vaccinia virus may be propagated using the methods described by Earl andMoss in Ausubel et al., 1994, which is incorporated by reference herein.

II. Proteinaceous and Nucleic Acid Compositions

The present invention concerns poxviruses, including those constructedwith one or more mutations compared to wild-type such that the virus hasdesirable properties for use against cancer cells, while being lesstoxic or non-toxic to non-cancer cells. Such poxviruses are described inU.S. Patent Application Publication Number 2006/0099224, which isincorporated herein by reference. The teachings described below providevarious protocols, by way of example, of implementing methods andcompositions of the invention, such as methods for generating mutatedviruses through the use of recombinant DNA technology.

In certain embodiments, the present invention concerns generatingpoxviruses that lack one or more functional polypeptides or proteinsand/or generating poxviruses that have the ability to release more of aparticular form of the virus, such as an infectious EEV form. In otherembodiments, the present invention concerns poxviruses and their use incombination with proteinaceous composition as part of a pharmaceuticallyacceptable formulation.

As used herein, a “protein” or “polypeptide” refers to a moleculecomprising at least one amino acid residue. In some embodiments, awild-type version of a protein or polypeptide are employed, however, inmany embodiments of the invention, a viral protein or polypeptide isabsent or altered so as to render the virus more useful for thetreatment of a cancer cells or cancer in a patient. The terms describedabove may be used interchangeably herein. A “modified protein” or“modified polypeptide” refers to a protein or polypeptide whose chemicalstructure is altered with respect to the wild-type protein orpolypeptide. In some embodiments, a modified protein or polypeptide hasat least one modified activity or function (recognizing that proteins orpolypeptides may have multiple activities or functions). The modifiedactivity or function may be reduced, diminished, eliminated, enhanced,improved, or altered in some other way (such as specificity) withrespect to that activity or function in a wild-type protein orpolypeptide. It is specifically contemplated that a modified protein orpolypeptide may be altered with respect to one activity or function yetretain wild-type activity or function in other respects. Alternatively,a modified protein may be completely nonfunctional or its cognatenucleic acid sequence may have been altered so that the polypeptide isno longer expressed at all, is truncated, or expresses a different aminoacid sequence as a result of a frameshift.

In certain embodiments the size of a mutated protein or polypeptide maycomprise, but is not limited to, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15,16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33,34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51,52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69,70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87,88, 89, 90, 91, 92, 93, 94, 95, 96, 97, 98, 99, 100, 110, 120, 130, 140,150, 160, 170, 180, 190, 200, 210, 220, 230, 240, 250, 275, 300, 325,350, 375, 400, 425, 450, 475, 500, 525, 550, 575, 600, 625, 650, 675,700, 725, 750, 775, 800, 825, 850, 875, 900, 925, 950, 975, 1000, 1100,1200, 1300, 1400, 1500, 1750, 2000, 2250, 2500 or greater amino moleculeresidues, and any range derivable therein. It is contemplated thatpolypeptides may be mutated by truncation, rendering them shorter thantheir corresponding wild-type form.

As used herein, an “amino molecule” refers to any amino acid, amino acidderivative or amino acid mimic as would be known to one of ordinaryskill in the art. In certain embodiments, the residues of theproteinaceous molecule are sequential, without any non-amino moleculeinterrupting the sequence of amino molecule residues. In otherembodiments, the sequence may comprise one or more non-amino moleculemoieties. In particular embodiments, the sequence of residues of theproteinaceous molecule may be interrupted by one or more non-aminomolecule moieties.

Accordingly, the term “proteinaceous composition” encompasses aminomolecule sequences comprising at least one of the 20 common amino acidsin naturally synthesized proteins, or at least one modified or unusualamino acid.

Proteinaceous compositions may be made by any technique known to thoseof skill in the art, including the expression of proteins, polypeptidesor peptides through standard molecular biological techniques, theisolation of proteinaceous compounds from natural sources, or thechemical synthesis of proteinaceous materials. The nucleotide andprotein, polypeptide and peptide sequences for various genes have beenpreviously disclosed, and may be found at computerized databases knownto those of ordinary skill in the art. One such database is the NationalCenter for Biotechnology Information's Genbank and GenPept databases(www.ncbi.nlm.nih.gov/). The coding regions for these known genes may beamplified and/or expressed using the techniques disclosed herein or aswould be know to those of ordinary skill in the art.

A. Functional Aspects

When the present application refers to the function or activity of viralproteins or polypeptides, it is meant to refer to the activity orfunction of that viral protein or polypeptide under physiologicalconditions, unless otherwise specified. For example, aninterferon-modulating polypeptide refers to a polypeptide that affectsat least one interferon and its activity, either directly or indirectly.The polypeptide may induce, enhance, raise, increase, diminish, weaken,reduce, inhibit, or mask the activity of an interferon, directly orindirectly. An example of directly affecting interferon involves, insome embodiments, an interferon-modulating polypeptide that specificallybinds to the interferon. Determination of which molecules possess thisactivity may be achieved using assays familiar to those of skill in theart. For example, transfer of genes encoding products that modulateinterferon, or variants thereof, into cells that are induced forinterferon activity compared to cells with such transfer of genes mayidentify, by virtue of different levels of an interferon response, thosemolecules having a interferon-modulating function.

It is specifically contemplated that a modulator may be a molecule thataffects the expression proteinaceous compositions involved in thetargeted molecule's pathway, such as by binding an interferon-encodingtranscript. Determination of which molecules are suitable modulators ofinterferon, IL-1β, TNF, or other molecules of therapeutic benefit may beachieved using assays familiar to those of skill in the art—some ofwhich are disclosed herein—and may include, for example, the use ofnative and/or recombinant viral proteins.

B. Variants of Viral Polypeptides

Amino acid sequence variants of the polypeptides of the presentinvention can be substitutional, insertional or deletion variants. Amutation in a gene encoding a viral polypeptide may affect 1, 2, 3, 4,5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23,24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41,42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59,60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77,78, 79, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95,96, 97, 98, 99, 100, 110, 120, 130, 140, 150, 160, 170, 180, 190, 200,210, 220, 230, 240, 250, 275, 300, 325, 350, 375, 400, 425, 450, 475,500 or more non-contiguous or contiguous amino acids of the polypeptide,as compared to wild-type. Various polypeptides encoded by Vaccinia virusmay be identified by reference to Rosel et al., 1986, Goebel et al.,1990 and GenBank Accession Number NC001559, each of which isincorporated herein by reference.

Deletion variants lack one or more residues of the native or wild-typeprotein. Individual residues can be deleted or all or part of a domain(such as a catalytic or binding domain) can be deleted. A stop codon maybe introduced (by substitution or insertion) into an encoding nucleicacid sequence to generate a truncated protein. Insertional mutantstypically involve the addition of material at a non-terminal point inthe polypeptide. This may include the insertion of an immunoreactiveepitope or simply one or more residues. Terminal additions, calledfusion proteins, may also be generated.

Substitutional variants typically contain the exchange of one amino acidfor another at one or more sites within the protein, and may be designedto modulate one or more properties of the polypeptide, with or withoutthe loss of other functions or properties. Substitutions may beconservative, that is, one amino acid is replaced with one of similarshape and charge. Conservative substitutions are well known in the artand include, for example, the changes of: alanine to serine; arginine tolysine; asparagine to glutamine or histidine; aspartate to glutamate;cysteine to serine; glutamine to asparagine; glutamate to aspartate;glycine to proline; histidine to asparagine or glutamine; isoleucine toleucine or valine; leucine to valine or isoleucine; lysine to arginine;methionine to leucine or isoleucine; phenylalanine to tyrosine, leucineor methionine; serine to threonine; threonine to serine; tryptophan totyrosine; tyrosine to tryptophan or phenylalanine; and valine toisoleucine or leucine. Alternatively, substitutions may benon-conservative such that a function or activity of the polypeptide isaffected. Non-conservative changes typically involve substituting aresidue with one that is chemically dissimilar, such as a polar orcharged amino acid for a nonpolar or uncharged amino acid, and viceversa.

The term “functionally equivalent codon” is used herein to refer tocodons that encode the same amino acid (see Table 1, below).

TABLE 1 Codon Table Amino Acids Codons Alanine Ala A GCA GCC GCG GCUCysteine Cys C UGC UGU Aspartic acid Asp D GAC GAU Glutamic acid Glu EGAA GAG Phenylalanine Phe F UUC UUU Glycine Gly G GGA GGC GGG GGUHistidine His H CAC CAU Isoleucine Ile I AUA AUC AUU Lysine Lys KAAA AAG Leucine Leu L UUA UUG CUA CUC CUG CUU Methionine Met M AUGAsparagine Asn N AAC AAU Proline Pro P CCA CCC CCG CCU Glutamine Gln QCAA CAG Arginine Arg R AGA AGG CGA CGC CGG CGU Serine Ser SAGC AGU UCA UCC UCG UCU Threonine Thr T ACA ACC ACG ACU Valine Val VGUA GUC GUG GUU Tryptophan Trp W UGG Tyrosine Tyr Y UAC UAU

It also will be understood that amino acid and nucleic acid sequencesmay include additional residues, such as additional N- or C-terminalamino acids or 5′ or 3′ sequences, and yet still be essentially as setforth in one of the sequences disclosed herein, so long as the sequencemeets the criteria set forth above, including the maintenance ofbiological protein activity where protein expression is concerned. Theaddition of terminal sequences particularly applies to nucleic acidsequences that may, for example, include various non-coding sequencesflanking either of the 5′ or 3′ portions of the coding region or mayinclude various internal sequences, i.e., introns, which are known tooccur within genes.

The following is a discussion based upon changing of the amino acids ofa protein to create an equivalent, or even an improved,second-generation molecule. For example, certain amino acids may besubstituted for other amino acids in a protein structure withoutappreciable loss of interactive binding capacity with structures suchas, for example, antigen-binding regions of antibodies or binding siteson substrate molecules. Since it is the interactive capacity and natureof a protein that defines that protein's biological functional activity,certain amino acid substitutions can be made in a protein sequence, andin its underlying DNA coding sequence, and nevertheless produce aprotein with like properties. It is thus contemplated by the inventorsthat various changes may be made in the DNA sequences of genes withoutappreciable loss of their biological utility or activity, as discussedbelow. Table 1 shows the codons that encode particular amino acids.

In making such changes, the hydropathic index of amino acids may beconsidered. The importance of the hydropathic amino acid index inconferring interactive biologic function on a protein is generallyunderstood in the art byte and Kyte and Doolittle, 1982). It is acceptedthat the relative hydropathic character of the amino acid contributes tothe secondary structure of the resultant protein, which in turn definesthe interaction of the protein with other molecules, for example,enzymes, substrates, receptors, DNA, antibodies, antigens, and the like.

It also is understood in the art that the substitution of like aminoacids can be made effectively on the basis of hydrophilicity. U.S. Pat.No. 4,554,101, incorporated herein by reference, states that thegreatest local average hydrophilicity of a protein, as governed by thehydrophilicity of its adjacent amino acids, correlates with a biologicalproperty of the protein. As detailed in U.S. Pat. No. 4,554,101, thefollowing hydrophilicity values have been assigned to amino acidresidues: arginine (+3.0); lysine (+3.0); aspartate (+3.0±); glutamate(+3.0±1); serine (+0.3); asparagine (+0.2); glutamine (+0.2); glycine(0); threonine (−0.4); proline (−0.5±1); alanine (−0.5); histidine*−0.5); cysteine (−1.0); methionine (−1.3); valine (−1.5); leucine(−1.8); isoleucine (−1.8); tyrosine (−2.3); phenylalanine (−2.5);tryptophan (−3.4).

It is understood that an amino acid can be substituted for anotherhaving a similar hydrophilicity value and still produce a biologicallyequivalent and immunologically equivalent protein. In such changes, thesubstitution of amino acids whose hydrophilicity values are within ±2 ispreferred, those that are within ±1 are particularly preferred, andthose within ±0.5 are even more particularly preferred.

As outlined above, amino acid substitutions generally are based on therelative similarity of the amino acid side-chain substituents, forexample, their hydrophobicity, hydrophilicity, charge, size, and thelike. Exemplary substitutions that take into consideration the variousforegoing characteristics are well known to those of skill in the artand include: arginine and lysine; glutamate and aspartate; serine andthreonine; glutamine and asparagine; and valine, leucine and isoleucine.

III. Nucleic Acid Molecules

A. Polynucleotides Encoding Native Proteins or Modified Proteins

The present invention concerns polynucleotides, isolatable from cells,that are capable of expressing all or part of a protein or polypeptide.In some embodiments of the invention, it concerns a viral genome thathas been specifically mutated to generate a virus that lacks certainfunctional viral polypeptides. The polynucleotides may encode a peptideor polypeptide containing all or part of a viral amino acid sequence orthey be engineered so they do not encode such a viral polypeptide orencode a viral polypeptide having at least one function or activityreduced, diminished, or absent. Recombinant proteins can be purifiedfrom expressing cells to yield active proteins. The genome, as well asthe definition of the coding regions of Vaccinia Virus may be found inRosel et al., 1986; Goebel et al., 1990; and/or GenBank Accession NumberNC_(—)001559, each of which is incorporated herein by reference.

As used herein, the term “DNA segment” refers to a DNA molecule that hasbeen isolated free of total genomic DNA of a particular species.Therefore, a DNA segment encoding a polypeptide refers to a DNA segmentthat contains wild-type, polymorphic, or mutant polypeptide-codingsequences yet is isolated away from, or purified free from, totalmammalian or human genomic DNA. Included within the term “DNA segment”are a polypeptide or polypeptides, DNA segments smaller than apolypeptide, and recombinant vectors, including, for example, plasmids,cosmids, phage, viruses, and the like.

As used in this application, the term “poxvirus polynucleotide” refersto a nucleic acid molecule encoding a poxvirus polypeptide that has beenisolated free of total genomic nucleic acid. Similarly, a “vacciniavirus polynucleotide” refers to a nucleic acid molecule encoding avaccinia virus polypeptide that has been isolated free of total genomicnucleic acid. A “poxvirus genome” or a “vaccinia virus genome” refers toa nucleic acid molecule that can be provided to a host cell to yield aviral particle, in the presence or absence of a helper virus. The genomemay or may have not been recombinantly mutated as compared to wild-typevirus.

The term “cDNA” is intended to refer to DNA prepared using messenger RNA(mRNA) as template. The advantage of using a cDNA, as opposed to genomicDNA or DNA polymerized from a genomic, non- or partially-processed RNAtemplate, is that the cDNA primarily contains coding sequences of thecorresponding protein. There may be times when the full or partialgenomic sequence is preferred, such as where the non-coding regions arerequired for optimal expression or where non-coding regions such asintrons are to be targeted in an antisense strategy.

It also is contemplated that a particular polypeptide from a givenspecies may be represented by natural variants that have slightlydifferent nucleic acid sequences but, nonetheless, encode the sameprotein (see Table 1 above).

Similarly, a polynucleotide comprising an isolated or purified wild-typeor mutant polypeptide gene refers to a DNA segment including wild-typeor mutant polypeptide coding sequences and, in certain aspects,regulatory sequences, isolated substantially away from other naturallyoccurring genes or protein encoding sequences. In this respect, the term“gene” is used for simplicity to refer to a functional protein,polypeptide, or peptide-encoding unit (including any sequences requiredfor proper transcription, post-translational modification, orlocalization). As will be understood by those in the art, thisfunctional term includes genomic sequences, cDNA sequences, and smallerengineered gene segments that express, or may be adapted to express,proteins, polypeptides, domains, peptides, fusion proteins, and mutants.A nucleic acid encoding all or part of a native or modified polypeptidemay contain a contiguous nucleic acid sequence encoding all or a portionof such a polypeptide of the following lengths: 10, 20, 30, 40, 50, 60,70, 80, 90, 100, 110, 120, 130, 140, 150, 160, 170, 180, 190, 200, 210,220, 230, 240, 250, 260, 270, 280, 290, 300, 310, 320, 330, 340, 350,360, 370, 380, 390, 400, 410, 420, 430, 440, 441, 450, 460, 470, 480,490, 500, 510, 520, 530, 540, 550, 560, 570, 580, 590, 600, 610, 620,630, 640, 650, 660, 670, 680, 690, 700, 710, 720, 730, 740, 750, 760,770, 780, 790, 800, 810, 820, 830, 840, 850, 860, 870, 880, 890, 900,910, 920, 930, 940, 950, 960, 970, 980, 990, 1000, 1010, 1020, 1030,1040, 1050, 1060, 1070, 1080, 1090, 1095, 1100, 1500, 2000, 2500, 3000,3500, 4000, 4500, 5000, 5500, 6000, 6500, 7000, 7500, 8000, 9000, 10000,or more nucleotides, nucleosides, or base pairs.

In particular embodiments, the invention concerns isolated DNA segmentsand recombinant vectors incorporating DNA sequences that encode awild-type or mutant poxvirus polypeptide or peptide that includes withinits amino acid sequence a contiguous amino acid sequence in accordancewith, or essentially corresponding to a native polypeptide. Thus, anisolated DNA segment or vector containing a DNA segment may encode, forexample, a INF modulator or TNF-modulating polypeptide that can inhibitor reduce INF activity. The term “recombinant” may be used inconjunction with a polypeptide or the name of a specific polypeptide,and this generally refers to a polypeptide produced from a nucleic acidmolecule that has been manipulated in vitro or that is the replicatedproduct of such a molecule.

In other embodiments, the invention concerns isolated DNA segments andrecombinant vectors incorporating DNA sequences that encode apolypeptide or peptide that includes within its amino acid sequence acontiguous amino acid sequence in accordance with, or essentiallycorresponding to the polypeptide.

The nucleic acid segments used in the present invention, regardless ofthe length of the coding sequence itself, may be combined with othernucleic acid sequences, such as promoters, polyadenylation signals,additional restriction enzyme sites, multiple cloning sites, othercoding segments, and the like, such that their overall length may varyconsiderably. It is therefore contemplated that a nucleic acid fragmentof almost any length may be employed, with the total length preferablybeing limited by the ease of preparation and use in the intendedrecombinant DNA protocol.

It is contemplated that the nucleic acid constructs of the presentinvention may encode full-length polypeptide from any source or encode atruncated version of the polypeptide, for example a truncated vacciniavirus polypeptide, such that the transcript of the coding regionrepresents the truncated version. The truncated transcript may then betranslated into a truncated protein. Alternatively, a nucleic acidsequence may encode a fill-length polypeptide sequence with additionalheterologous coding sequences, for example to allow for purification ofthe polypeptide, transport, secretion, post-translational modification,or for therapeutic benefits such as targetting or efficacy. As discussedabove, a tag or other heterologous polypeptide may be added to themodified polypeptide-encoding sequence, wherein “heterologous” refers toa polypeptide that is not the same as the modified polypeptide.

In a non-limiting example, one or more nucleic acid constructs may beprepared that include a contiguous stretch of nucleotides identical toor complementary to the a particular gene, such as the B18R gene. Anucleic acid construct may be at least 20, 30, 40, 50, 60, 70, 80, 90,100, 110, 120, 130, 140, 150, 160, 170, 180, 190, 200, 250, 300, 400,500, 600, 700, 800, 900, 1,000, 2,000, 3,000, 4,000, 5,000, 6,000,7,000, 8,000, 9,000, 10,000, 15,000, 20,000, 30,000, 50,000, 100,000,250,000, 500,000, 750,000, to at least 1,000,000 nucleotides in length,as well as constructs of greater size, up to and including chromosomalsizes (including all intermediate lengths and intermediate ranges),given the advent of nucleic acids constructs such as a yeast artificialchromosome are known to those of ordinary skill in the art. It will bereadily understood that “intermediate lengths” and “intermediateranges,” as used herein, means any length or range including or betweenthe quoted values (i.e., all integers including and between suchvalues).

The DNA segments used in the present invention encompass biologicallyfunctional equivalent modified polypeptides and peptides, for example, amodified gelonin toxin. Such sequences may arise as a consequence ofcodon redundancy and functional equivalency that are known to occurnaturally within nucleic acid sequences and the proteins thus encoded.Alternatively, functionally equivalent proteins or peptides may becreated via the application of recombinant DNA technology, in whichchanges in the protein structure may be engineered, based onconsiderations of the properties of the amino acids being exchanged.Changes designed by human may be introduced through the application ofsite-directed mutagenesis techniques, e.g., to introduce improvements tothe antigenicity of the protein, to reduce toxicity effects of theprotein in vivo to a subject given the protein, or to increase theefficacy of any treatment involving the protein.

In certain other embodiments, the invention concerns isolated DNAsegments and recombinant vectors that include within their sequence acontiguous nucleic acid sequence from that shown in sequences identifiedherein (and/or incorporated by reference). Such sequences, however, maybe mutated to yield a protein product whose activity is altered withrespect to wild-type.

It also will be understood that this invention is not limited to theparticular nucleic acid and amino acid sequences of these identifiedsequences. Recombinant vectors and isolated DNA segments may thereforevariously include the poxvirus-coding regions themselves, coding regionsbearing selected alterations or modifications in the basic codingregion, or they may encode larger polypeptides that nevertheless includepoxvirus-coding regions or may encode biologically functional equivalentproteins or peptides that have variant amino acids sequences.

The DNA segments of the present invention encompass biologicallyfunctional equivalent poxvirus proteins and peptides. Such sequences mayarise as a consequence of codon redundancy and functional equivalencythat are known to occur naturally within nucleic acid sequences and theproteins thus encoded. Alternatively, functionally equivalent proteinsor peptides may be created via the application of recombinant DNAtechnology, in which changes in the protein structure may be engineered,based on considerations of the properties of the amino acids beingexchanged. Changes designed by man may be introduced through theapplication of site-directed mutagenesis techniques, e.g., to introduceimprovements to the antigenicity of the protein.

B. Mutagenesis of Poxvirus Polynucleotides

In various embodiments, the poxvirus polynucleotide may be altered ormutagenized. Alterations or mutations may include insertions, deletions,point mutations, inversions, and the like and may result in themodulation, activation and/or inactivation of certain pathways ormolecular mechanisms, as well as altering the function, location, orexpression of a gene product, in particular rendering a gene productnon-functional. Where employed, mutagenesis of a polynucleotide encodingall or part of a Poxvirus may be accomplished by a variety of standard,mutagenic procedures (Sambrook et al., 1989).

Mutation is the process whereby changes occur in the quantity orstructure of an organism. Mutation can involve modification of thenucleotide sequence of a single gene, blocks of genes or wholechromosome. Changes in single genes may be the consequence of pointmutations which involve the removal, addition or substitution of asingle nucleotide base within a DNA sequence, or they may be theconsequence of changes involving the insertion or deletion of largenumbers of nucleotides.

Mutations may be induced following exposure to chemical or physicalmutagens. Such mutation-inducing agents include ionizing radiation,ultraviolet light and a diverse array of chemical such as alkylatingagents and polycyclic aromatic hydrocarbons all of which are capable ofinteracting either directly or indirectly (generally following somemetabolic biotransformations) with nucleic acids. The DNA damage inducedby such agents may lead to modifications of base sequence when theaffected DNA is replicated or repaired and thus to a mutation. Mutationalso can be site-directed through the use of particular targetingmethods.

C. Vectors

To generate mutations in the poxvirus genome, native and modifiedpolypeptides may be encoded by a nucleic acid molecule comprised in avector. The term “vector” is used to refer to a carrier nucleic acidmolecule into which an exogenous nucleic acid sequence can be insertedfor introduction into a cell where it can be replicated. A nucleic acidsequence can be “exogenous,” which means that it is foreign to the cellinto which the vector is being introduced or that the sequence ishomologous to a sequence in the cell but in a position within the hostcell nucleic acid in which the sequence is ordinarily not found. Vectorsinclude plasmids, cosmids, viruses (bacteriophage, animal viruses, andplant viruses), and artificial chromosomes (e.g., YACs). One of skill inthe art would be well equipped to construct a vector through standardrecombinant techniques, which are described in Sambrook et al., (1989)and Ausubel et al., 1994, both incorporated herein by reference. Inaddition to encoding a modified polypeptide such as modified gelonin, avector may encode non-modified polypeptide sequences such as a tag ortargeting molecule. Useful vectors encoding such fusion proteins includepIN vectors (Inouye et al., 1985), vectors encoding a stretch ofhistidines, and pGEX vectors, for use in generating glutathioneS-transferase (GST) soluble fusion proteins for later purification andseparation or cleavage. A targeting molecule is one that directs themodified polypeptide to a particular organ, tissue, cell, or otherlocation in a subject's body.

The term “expression vector” refers to a vector containing a nucleicacid sequence coding for at least part of a gene product capable ofbeing transcribed. In some cases, RNA molecules are then translated intoa protein, polypeptide, or peptide. In other cases, these sequences arenot translated, for example, in the production of antisense molecules orribozymes. Expression vectors can contain a variety of “controlsequences,” which refer to nucleic acid sequences necessary for thetranscription and possibly translation of an operably linked codingsequence in a particular host organism. In addition to control sequencesthat govern transcription and translation, vectors and expressionvectors may contain nucleic acid sequences that serve other functions aswell and are described infra.

1. Promoters and Enhancers

A “promoter” is a control sequence that is a region of a nucleic acidsequence at which initiation and rate of transcription are controlled.It may contain genetic elements at which regulatory proteins andmolecules may bind such as RNA polymerase and other transcriptionfactors. The phrases “operatively positioned,” “operatively linked,”“under control,” and “under transcriptional control” mean that apromoter is in a correct functional location and/or orientation inrelation to a nucleic acid sequence to control transcriptionalinitiation and/or expression of that sequence. A promoter may or may notbe used in conjunction with an “enhancer,” which refers to a cis-actingregulatory sequence involved in the transcriptional activation of anucleic acid sequence.

A promoter may be one naturally associated with a gene or sequence, asmay be obtained by isolating the 5′ non-coding sequences locatedupstream of the coding segment and/or exon. Such a promoter can bereferred to as “endogenous.” Similarly, an enhancer may be one naturallyassociated with a nucleic acid sequence, located either downstream orupstream of that sequence. Alternatively, certain advantages will begained by positioning the coding nucleic acid segment under the controlof a recombinant or heterologous promoter, which refers to a promoterthat is not normally associated with a nucleic acid sequence in itsnatural environment. A recombinant or heterologous enhancer refers alsoto an enhancer not normally associated with a nucleic acid sequence inits natural environment. Such promoters or enhancers may includepromoters or enhancers of other genes, and promoters or enhancersisolated from any other prokaryotic, viral, or eukaryotic cell, andpromoters or enhancers not “naturally occurring,” i.e., containingdifferent elements of different transcriptional regulatory regions,and/or mutations that alter expression. In addition to producing nucleicacid sequences of promoters and enhancers synthetically, sequences maybe produced using recombinant cloning and/or nucleic acid amplificationtechnology, including PCR™, in connection with the compositionsdisclosed herein (see U.S. Pat. No. 4,683,202, U.S. Pat. No. 5,928,906,each incorporated herein by reference). Furthermore, it is contemplatedthe control sequences that direct transcription and/or expression ofsequences within non-nuclear organelles such as mitochondria,chloroplasts, and the like, can be employed as well.

Naturally, it may be important to employ a promoter and/or enhancer thateffectively directs the expression of the DNA segment in the cell type,organelle, and organism chosen for expression. Those of skill in the artof molecular biology generally know the use of promoters, enhancers, andcell type combinations for protein expression, for example, see Sambrooket al. (1989), incorporated herein by reference. The promoters employedmay be constitutive, tissue-specific, inducible, and/or useful under theappropriate conditions to direct high level expression of the introducedDNA segment, such as is advantageous in the large-scale production ofrecombinant proteins and/or peptides. The promoter may be heterologousor endogenous.

The identity of tissue-specific promoters or elements, as well as assaysto characterize their activity, is well known to those of skill in theart. Examples of such regions include the human LIMK2 gene (Nomoto etal. 1999), the somatostatin receptor 2 gene (Kraus et al., 1998), murineepididymal retinoic acid-binding gene (Lareyre et al., 1999), human CD4(Zhao-Emonet et al., 1998), mouse α2 (XI) collagen (Tsumaki, et al.,1998), DIA dopamine receptor gene (Lee, et al., 1997), insulin-likegrowth factor II (Wu et al., 1997), human platelet endothelial celladhesion molecule-1 (Almendro et al., 1996), and the SM22a promoter.

2. Initiation Signals and Internal Ribosome Binding Sites

A specific initiation signal also may be required for efficienttranslation of coding sequences. These signals include the ATGinitiation codon or adjacent sequences. Exogenous translational controlsignals, including the ATG initiation codon, may need to be provided.One of ordinary skill in the art would readily be capable of determiningthis and providing the necessary signals. It is well known that theinitiation codon must be “in-frame” with the reading frame of thedesired coding sequence to ensure translation of the entire insert. Theexogenous translational control signals and initiation codons can beeither natural or synthetic. The efficiency of expression may beenhanced by the inclusion of appropriate transcription enhancerelements.

In certain embodiments of the invention, the use of internal ribosomeentry sites (IRES) elements are used to create multigene, orpolycistronic, messages. IRES elements are able to bypass the ribosomescanning model of 5′-methylated Cap dependent translation and begintranslation at internal sites (Pelletier and Sonenberg, 1988). IRESelements from two members of the picornavirus family (polio andencephalomyocarditis) have been described (Pelletier and Sonenberg,1988), as well an IRES from a mammalian message (Macejak and Sarnow,1991). IRES elements can be linked to heterologous open reading flames.Multiple open reading frames can be transcribed together, each separatedby an IRES, creating polycistronic messages. By virtue of the IRESelement, each open reading frame is accessible to ribosomes forefficient translation. Multiple genes can be efficiently expressed usinga single promoter/enhancer to transcribe a single message (see U.S. Pat.Nos. 5,925,565 and 5,935,819, herein incorporated by reference).

3. Multiple Cloning Sites

Vectors can include a multiple cloning site (NCS), which is a nucleicacid region that contains multiple restriction enzyme sites, any ofwhich can be used in conjunction with standard recombinant technology todigest the vector. (See Carbonelli et al., 1999, Levenson et al., 1998,and Cocea, 1997, incorporated herein by reference.) “Restriction enzymedigestion” refers to catalytic cleavage of a nucleic acid molecule withan enzyme that functions only at specific locations in a nucleic acidmolecule. Many of these restriction enzymes are commercially available.Use of such enzymes is widely understood by those of skill in the art.Frequently, a vector is linearized or fragmented using a restrictionenzyme that cuts within the MCS to enable exogenous sequences to beligated to the vector. “Ligation” refers to the process of formingphosphodiester bonds between two nucleic acid fragments, which may ormay not be contiguous with each other. Techniques involving restrictionenzymes and ligation reactions are well known to those of skill in theart of recombinant technology.

4. Splicing Sites

Most transcribed eukaryotic RNA molecules will undergo RNA splicing toremove introns from the primary transcripts. Vectors containing genomiceukaryotic sequences may require donor and/or acceptor splicing sites toensure proper processing of the transcript for protein expression. (SeeChandler et al., 1997, incorporated herein by reference.)

5. Termination Signals

The vectors or constructs of the present invention will generallycomprise at least one termination signal. A “termination signal” or“terminator” is comprised of the DNA sequences involved in specifictermination of an RNA transcript by an RNA polymerase. Thus, in certainembodiments a termination signal that ends the production of an RNAtranscript is contemplated. A terminator may be necessary in vivo toachieve desirable message levels.

In eukaryotic systems, the terminator region may also comprise specificDNA sequences that permit site-specific cleavage of the new transcriptso as to expose a polyadenylation site. This signals a specializedendogenous polymerase to add a stretch of about 200 A residues (polyA)to the 3′ end of the transcript. RNA molecules modified with this polyAtail appear to more stable and are translated more efficiently. Thus, inother embodiments involving eukaryotes, it is preferred that thatterminator comprises a signal for the cleavage of the RNA, and it ismore preferred that the terminator signal promotes polyadenylation ofthe message. The terminator and/or polyadenylation site elements canserve to enhance message levels and/or to minimize read through from thecassette into other sequences.

Terminators contemplated for use in the invention include any knownterminator of transcription described herein or known to one of ordinaryskill in the art, including but not limited to, for example, thetermination sequences of genes, such as for example the bovine growthhormone terminator or viral termination sequences, such as for examplethe SV40 terminator. In certain embodiments, the termination signal maybe a lack of transcribable or translatable sequence, such as due to asequence truncation.

6. Polyadenylation Signals

In expression, particularly eukaryotic expression, one will typicallyinclude a polyadenylation signal to effect proper polyadenylation of thetranscript. The nature of the polyadenylation signal is not believed tobe crucial to the successful practice of the invention, and/or any suchsequence may be employed. Preferred embodiments include the SV40polyadenylation signal and/or the bovine growth hormone polyadenylationsignal, convenient and/or known to function well in various targetcells. Polyadenylation may increase the stability of the transcript ormay facilitate cytoplasmic transport.

7. Origins of Replication

In order to propagate a vector in a host cell, it may contain one ormore origins of replication sites (often termed “ori”), which is aspecific nucleic acid sequence at which replication is initiated.Alternatively an autonomously replicating sequence (ARS) can be employedif the host cell is yeast.

8. Selectable and Screenable Markers

In certain embodiments of the invention, cells containing a nucleic acidconstruct of the present invention may be identified in vitro or in vivoby including a marker in the expression vector. Such markers wouldconfer an identifiable change to the cell permitting easy identificationof cells containing the expression vector. Generally, a selectablemarker is one that confers a property that allows for selection. Apositive selectable marker is one in which the presence of the markerallows for its selection, while a negative selectable marker is one inwhich its presence prevents its selection. An example of a positiveselectable marker is a drug resistance marker.

Usually the inclusion of a drug selection marker aids in the cloning andidentification of transformants, for example, genes that conferresistance to neomycin, puromycin, hygromycin, DHFR, GPT, zeocin andhistidinol are useful selectable markers. In addition to markersconferring a phenotype that allows for the discrimination oftransformants based on the implementation of conditions, other types ofmarkers including screenable markers such as GFP, whose basis iscolorimetric analysis, are also contemplated. Alternatively, screenableenzymes such as herpes simplex virus thymidine kinase (tk) orchloramphenicol acetyltransferase (CAT) may be utilized. One of skill inthe art would also know how to employ immunologic markers, possibly inconjunction with FACS analysis. The marker used is not believed to beimportant, so long as it is capable of being expressed simultaneouslywith the nucleic acid encoding a gene product. Further examples ofselectable and screenable markers are well known to one of skill in theart.

D. Host Cells

As used herein, the terms “cell,” “cell line,” and “cell culture” may beused interchangeably. All of these terms also include their progeny,which is any and all subsequent generations. It is understood that allprogeny may not be identical due to deliberate or inadvertent mutations.In the context of expressing a heterologous nucleic acid sequence, “hostcell” refers to a prokaryotic or eukaryotic cell, and it includes anytransformable organisms that is capable of replicating a vector and/orexpressing a heterologous gene encoded by a vector. A host cell can, andhas been, used as a recipient for vectors or viruses (which does notqualify as a vector if it expresses no exogenous polypeptides). A hostcell may be “transfected” or “transformed,” which refers to a process bywhich exogenous nucleic acid, such as a modified protein-encodingsequence, is transferred or introduced into the host cell. A transformedcell includes the primary subject cell and its progeny.

Host cells may be derived from prokaryotes or eukaryotes, includingyeast cells, insect cells, and mammalian cells, depending upon whetherthe desired result is replication of the vector or expression of part orall of the vector-encoded nucleic acid sequences. Numerous cell linesand cultures are available for use as a host cell, and they can beobtained through the American Type Culture Collection (ATCC), which isan organization that serves as an archive for living cultures andgenetic materials (www.atcc.org). An appropriate host can be determinedby one of skill in the art based on the vector backbone and the desiredresult. A plasmid or cosmid, for example, can be introduced into aprokaryote host cell for replication of many vectors. Bacterial cellsused as host cells for vector replication and/or expression includeDH5α, JM109, and KCB, as well as a number of commercially availablebacterial hosts such as SURE® Competent Cells and SOLOPACK™ Gold Cells(STRATAGENE®, La Jolla, Calif.). Alternatively, bacterial cells such asE. coli LE392 could be used as host cells for phage viruses. Appropriateyeast cells include Saccharomyces cerevisiae, Saccharomyces pombe, andPichia pastoris.

Examples of eukaryotic host cells for replication and/or expression of avector include HeLa, NIH3T3, Jurkat, 293, Cos, CHO, Saos, and PC12. Manyhost cells from various cell types and organisms are available and wouldbe known to one of skill in the art. Similarly, a viral vector may beused in conjunction with either a eukaryotic or prokaryotic host cell,particularly one that is permissive for replication or expression of thevector.

Some vectors may employ control sequences that allow it to be replicatedand/or expressed in both prokaryotic and eukaryotic cells. One of skillin the art would further understand the conditions under which toincubate all of the above described host cells to maintain them and topermit replication of a vector. Also understood and known are techniquesand conditions that would allow large-scale production of vectors, aswell as production of the nucleic acids encoded by vectors and theircognate polypeptides, proteins, or peptides.

E. Methods of Gene Transfer

Suitable methods for nucleic acid delivery to effect expression ofcompositions of the present invention are believed to include virtuallyany method by which a nucleic acid (e.g., DNA, including viral andnon-viral vectors) can be introduced into an organelle, a cell, a tissueor an organism, as described herein or as would be known to one ofordinary skill in the art. Such methods include, but are not limited to,direct delivery of DNA such as by injection (U.S. Pat. Nos. 5,994,624,5,981,274, 5,945,100, 5,780,448, 5,736,524, 5,702,932, 5,656,610,5,589,466 and 5,580,859, each incorporated herein by reference),including microinjection (Harland and Weintraub, 1985; U.S. Pat. No.5,789,215, incorporated herein by reference); by electroporation (U.S.Pat. No. 5,384,253, incorporated herein by reference); by calciumphosphate precipitation (Graham and Van Der Eb, 1973; Chen and Okayama,1987; Rippe et al., 1990); by using DEAE-dextran followed bypolyethylene glycol (Gopal, 1985); by direct sonic loading (Fechheimeret al., 1987); by liposome mediated transfection (Nicolau and Sene,1982; Fraley et al., 1979; Nicolau et al., 1987; Wong et al., 1980;Kaneda et al., 1989; Kato et al., 1991); by microprojectile bombardment(PCT Application Nos. WO 94/09699 and 95/06128; U.S. Pat. Nos.5,610,042; 5,322,783, 5,563,055, 5,550,318, 5,538,877 and 5,538,880, andeach incorporated herein by reference); by agitation with siliconcarbide fibers (Kaeppler et al., 1990; U.S. Pat. Nos. 5,302,523 and5,464,765, each incorporated herein by reference); byAgrobacterium-mediated transformation (U.S. Pat. Nos. 5,591,616 and5,563,055, each incorporated herein by reference); or by PEG-mediatedtransformation of protoplasts (Omirulleh et al., 1993; U.S. Pat. Nos.4,684,611 and 4,952,500, each incorporated herein by reference); bydesiccation/inhibition-mediated DNA uptake (Potrykus et al., 1985).Through the application of techniques such as these, organelle(s),cell(s), tissue(s) or organism(s) may be stably or transientlytransformed.

F. Lipid Components and Moieties

In certain embodiments, the present invention concerns compositionscomprising one or more lipids associated with a nucleic acid, an aminoacid molecule, such as a peptide, or another small molecule compound. Inany of the embodiments discussed herein, the molecule may be either apoxvirus polypeptide or a poxvirus polypeptide modulator, for example anucleic acid encoding all or part of either a poxvirus polypeptide, oralternatively, an amino acid molecule encoding all or part of poxviruspolypeptide modulator. A lipid is a substance that is characteristicallyinsoluble in water and extractable with an organic solvent. Compoundsthan those specifically described herein are understood by one of skillin the art as lipids, and are encompassed by the compositions andmethods of the present invention. A lipid component and a non-lipid maybe attached to one another, either covalently or non-covalently.

A lipid may be naturally-occurring or synthetic (i.e., designed orproduced by man). However, a lipid is usually a biological substance.Biological lipids are well known in the art, and include for example,neutral fats, phospholipids, phosphoglycerides, steroids, terpenes,lysolipids, glycosphingolipids, glucolipids, sulphatides, lipids withether and ester-linked fatty acids and polymerizable lipids, andcombinations thereof.

A nucleic acid molecule or amino acid molecule, such as a peptide,associated with a lipid may be dispersed in a solution containing alipid, dissolved with a lipid, emulsified with a lipid, mixed with alipid, combined with a lipid, covalently bonded to a lipid, contained asa suspension in a lipid or otherwise associated with a lipid. A lipid orlipid/poxvirus-associated composition of the present invention is notlimited to any particular structure. For example, they may also simplybe interspersed in a solution, possibly forming aggregates which are notuniform in either size or shape. In another example, they may be presentin a bilayer structure, as micelles, or with a “collapsed” structure. Inanother non-limiting example, a lipofectamine(Gibco BRL)-poxvirus orSuperfect (Qiagen)-poxvirus complex is also contemplated.

In certain embodiments, a lipid composition may comprise about 1%, about2%, about 3%, about 4% about 5%, about 6%, about 7%, about 8%, about 9%,about 10%, about 11%, about 12%, about 13%, about 14%, about 15%, about16%, about 17%, about 18%, about 19%, about 20%, about 21%, about 22%,about 23%, about 24%, about 25%, about 26%, about 27%, about 28%, about29%, about 30%, about 31%, about 32%, about 33%, about 34%, about 35%,about 36%, about 37%, about 38%, about 39%, about 40%, about 41%, about42%, about 43%, about 44%, about 45%, about 46%, about 47%, about 48%,about 49%, about 50%, about 51%, about 52%, about 53%, about 54%, about55%, about 56%, about 57%, about 58%, about 59%, about 60%, about 61%,about 62%, about 63%, about 64%, about 65%, about 66%, about 67%, about68%, about 69%, about 70%, about 71%, about 72%, about 73%, about 74%,about 75%, about 76%, about 77%, about 78%, about 79%, about 80%, about81%, about 82%, about 83%, about 84%, about 85%, about 86%, about 87%,about 88%, about 89%, about 90%, about 91%, about 92%, about 93%, about94%, about 95%, about 96%, about 97%, about 98%, about 99%, about 100%,or any range derivable therein, of a particular lipid, lipid type ornon-lipid component such as a drug, protein, sugar, nucleic acids orother material disclosed herein or as would be known to one of skill inthe art. In a non-limiting example, a lipid composition may compriseabout 10% to about 20% neutral lipids, and about 33% to about 34% of acerebroside, and about 1% cholesterol. In another non-limiting example,a liposome may comprise about 4% to about 12% terpenes, wherein about 1%of the micelle is specifically lycopene, leaving about 3% to about 11%of the liposome as comprising other terpenes; and about 10% to about 35%phosphatidyl choline, and about 1% of a drug. Thus, it is contemplatedthat lipid compositions of the present invention may comprise any of thelipids, lipid types or other components in any combination or percentagerange.

G. GM-CSF

In a particular aspect of the invention, the vaccinia viruses will carrya gene encoding for GM-CSF. GM-CSF is granulocyte-macrophagecolony-stimulating factor, a substance that helps make more white bloodcells, especially granulocytes, macrophages, and cells that becomeplatelets. It is a cytokine that belongs to the family of drugs calledhematopoietic (blood-forming) agents, and is also known as sargramostim.GM-CSF was first cloned and sequence in 1985 by Cantrell et al. (1985).Human GM-CSF is a 144-amino acid glycoprotein encoded by a singleopen-reading frame with a predicted molecular mass of 16,293 daltons. Itexhibits a 69% nucleotide homology and 54% amino acid homology to mouseGM-CSF and exists as a single-copy gene.

GM-CSF is produced by a number of different cell types (includingactivated T cells, B cells, macrophages, mast cells, endothelial cellsand fibroblasts) in response to cytokine or immune and inflammatorystimuli. Besides granulocyte-macrophage progenitors, GM-CSF is also agrowth factor for erythroid, megakaryocyte and eosinophil progenitors.On mature hematopoietic cells, GM-CSF is a survival factor for andactivates the effector functions of granulocytes, monocytes/macrophagesand eosinophils. GM-CSF has also been reported to have a functional roleon non-hematopoietic cells. It can induce human endothelial cells tomigrate and proliferate.

GM-CSF is species specific and human GM-CSF has no biological effects onmouse cells. GM-CSF exerts its biological effects through binding tospecific cell surface receptors. The high affinity receptors requiredfor human GM-CSF signal transduction have been shown to be heterodimersconsisting of a GM-CSF-specific α chain and a common β chain that isshared by the high-affinity receptors for IL-3 and IL-5.

Although GM-CSF can stimulate the proliferation of a number of tumorcell lines, including osteogenic sarcoma, carcinoma and adenocarcinomacell lines, clinical trials of GM-CSF (alone or with otherimmunotherapies) are in progress for people with melanoma, leukemia,lymphoma, neuroblastoma, Kaposi sarcoma, mesothelioma, lung cancer,breast cancer, prostate cancer, colorectal cancer, brain tumors, kidneycancer and cervical cancer. Common side effects of GM-CSF includeflu-like symptoms (fever, headaches, muscle aches), rashes, facialflushing, and bone pain.

H. Other Heterologous Genes

In some embodiments, the vaccinia virus used in methods of the inventioncontains a nucleic acid sequence that expresses a heterologous sequencethat does not encode GM-CSF but encodes another heterologous sequence.In certain embodiments, the heterologous sequence encodes anothercytokine. Alternatively or additionally, the vaccinia virus may containa nucleic acid that encodes for IL-12, thymidine deaminase, TNF, and thelike. In addition, any gene product discussed herein may be encoded by anucleic acid contained within a vaccinia virus and used in methods ofthe invention.

IV. Pharmaceutical Formulations, Delivery and Treatment Regimens

In an embodiment of the present invention, a method of treatment for ahyperproliferative disease, such as cancer, by the delivery of analtered poxvirus, such as vaccinia virus, is contemplated. Examples ofcancer contemplated for treatment include liver cancer, lung cancer,head and neck cancer, breast cancer, pancreatic cancer, prostate cancer,renal cancer, bone cancer, testicular cancer, cervical cancer,gastrointestinal cancer, lymphomas, pre-neoplastic lesions in the lung,colon cancer, melanoma, bladder cancer and any other cancers or tumorsthat may be treated.

An effective amount of the pharmaceutical composition is defined hereinas that amount sufficient to induce oncolysis, the disruption or lysisof a cancer cell, as well as slowing, inhibition or reduction in thegrowth or size of a tumor and includes the eradication of the tumor incertain instances. An effective amount can also encompass an amount thatresults in systemic dissemination of the therapeutic virus to tumorsindirectly, e.g., infection of non-injected tumors.

Preferably, patients will have adequate bone marrow function (defined asa peripheral absolute granulocyte count of >2,000/mm³ and a plateletcount of 100,000/mm³), adequate liver function (bilirubin <1.5 mg/dl)and adequate renal function (creatinine <1.5 mg/dl).

Cancer cells that may be treated by methods and compositions of theinvention include cells from the bladder, blood, bone, bone marrow,brain, breast, colon, esophagus, gastrointestine, gum, head, kidney,liver, lung, nasopharynx, neck, ovary, prostate, skin, stomach, testis,tongue, or uterus. In addition, the cancer may specifically be of thefollowing histological type, though it is not limited to these:neoplasm, malignant; carcinoma; carcinoma, undifferentiated; giant andspindle cell carcinoma; small cell carcinoma; papillary carcinoma;squamous cell carcinoma; lymphoepithelial carcinoma; basal cellcarcinoma; pilomatrix carcinoma; transitional cell carcinoma; papillarytransitional cell carcinoma; adenocarcinoma; gastrinoma, malignant;cholangiocarcinoma; hepatocellular carcinoma; combined hepatocellularcarcinoma and cholangiocarcinoma; trabecular adenocarcinoma; adenoidcystic carcinoma; adenocarcinoma in adenomatous polyp; adenocarcinoma,familial polyposis coli; solid carcinoma; carcinoid tumor, malignant;branchiolo-alveolar adenocarcinoma; papillary adenocarcinoma;chromophobe carcinoma; acidophil carcinoma; oxyphilic adenocarcinoma;basophil carcinoma; clear cell adenocarcinoma; granular cell carcinoma;follicular adenocarcinoma; papillary and follicular adenocarcinoma;nonencapsulating sclerosing carcinoma; adrenal cortical carcinoma;endometroid carcinoma; skin appendage carcinoma; apocrineadenocarcinoma; sebaceous adenocarcinoma; ceruminous adenocarcinoma;mucoepidermoid carcinoma; cystadenocarcinoma; papillarycystadenocarcinoma; papillary serous cystadenocarcinoma; mucinouscystadenocarcinoma; mucinous adenocarcinoma; signet ring cell carcinoma;infiltrating duct carcinoma; medullary carcinoma; lobular carcinoma;inflammatory carcinoma; paget's disease, mammary; acinar cell carcinoma;adenosquamous carcinoma; adenocarcinoma w/squamous metaplasia; thymoma,malignant; ovarian stromal tumor, malignant; thecoma, malignant;granulosa cell tumor, malignant; androblastoma, malignant; sertoli cellcarcinoma; leydig cell tumor, malignant; lipid cell tumor, malignant;paraganglioma, malignant; extra-mammary paraganglioma, malignant;pheochromocytoma; glomangiosarcoma; malignant melanoma; amelanoticmelanoma; superficial spreading melanoma; malig melanoma in giantpigmented nevus; epithelioid cell melanoma; blue nevus, malignant;sarcoma; fibrosarcoma; fibrous histiocytoma, malignant; myxosarcoma;liposarcoma; leiomyosarcoma; rhabdomyosarcoma; embryonalrhabdomyosarcoma; alveolar rhabdomyosarcoma; stromal sarcoma; mixedtumor, malignant; mullerian mixed tumor; nephroblastoma; hepatoblastoma;carcinosarcoma; mesenchymoma, malignant; brenner tumor, malignant;phyllodes tumor, malignant; synovial sarcoma; mesothelioma, malignant;dysgerminoma; embryonal carcinoma; teratoma, malignant; struma ovarii,malignant; choriocarcinoma; mesonephroma, malignant; hemangiosarcoma;hemangioendothelioma, malignant; Kaposi's sarcoma; hemangiopericytoma,malignant; lymphangiosarcoma; osteosarcoma; juxtacortical osteosarcoma;chondrosarcoma; chondroblastoma, malignant; mesenchymal chondrosarcoma;giant cell tumor of bone; Ewing's sarcoma; odontogenic tumor, malignant;ameloblastic odontosarcoma; ameloblastoma, malignant; ameloblasticfibrosarcoma; pinealoma, malignant; chordoma; glioma, malignant;ependymoma; astrocytoma; protoplasmic astrocytoma; fibrillaryastrocytoma; astroblastoma; glioblastoma; oligodendroglioma;oligodendroblastoma; primitive neuroectodermal; cerebellar sarcoma;ganglioneuroblastoma; neuroblastoma; retinoblastoma; olfactoryneurogenic tumor; meningioma, malignant; neurofibrosarcoma;neurilemmoma, malignant; granular cell tumor, malignant; malignantlymphoma; hodgkin's disease; hodgkin's; paragranuloma; malignantlymphoma, small lymphocytic; malignant lymphoma, large cell, diffuse;malignant lymphoma, follicular; mycosis fungoides; other specifiednon-hodgkin's lymphomas; malignant histiocytosis; multiple myeloma; mastcell sarcoma; immunoproliferative small intestinal disease; leukemia;lymphoid leukemia; plasma cell leukemia; erythroleukemia; lymphosarcomacell leukemia; myeloid leukemia; basophilic leukemia; eosinophilicleukemia; monocytic leukemia; mast cell leukemia; megakaryoblasticleukemia; myeloid sarcoma; and hairy cell leukemia.

The present invention contemplates methods for inhibiting or preventinglocal invasiveness and/or metastasis of any type of primary cancer. Forexample, the primary cancer may be melanoma, non-small cell lung,small-cell lung, lung, hepatocarcinoma, retinoblastoma, astrocytoma,glioblastoma, gum, tongue, leukemia, neuroblastoma, head, neck, breast,pancreatic, prostate, renal, bone, testicular, ovarian, mesothelioma,cervical, gastrointestinal, lymphoma, brain, colon, or bladder. Incertain embodiments of the present invention, the primary cancer is lungcancer. For example, the lung cancer may be non-small cell lungcarcinoma.

Moreover, the present invention can be used to prevent cancer or totreat pre-cancers or premalignant cells, including metaplasias,dysplasias, and hyperplasias. It may also be used to inhibit undesirablebut benign cells, such as squamous metaplasia, dysplasia, benignprostate hyperplasia cells, hyperplastic lesions, and the like. Theprogression to cancer or to a more severe form of cancer may be halted,disrupted, or delayed by methods of the invention involving GM-CSFpolypeptides or other polypeptide(s) encoded by a vaccinia virus, asdiscussed herein.

A. Administration

To induce oncolysis, kill cells, inhibit growth, inhibit metastases,decrease tumor size and otherwise reverse or reduce the malignantphenotype of tumor cells, using the methods and compositions of thepresent invention, one would contact a tumor with the poxvirusexpressing GM-CSF. The routes of administration will vary, naturally,with the location and nature of the lesion, and include, e.g.,intradermal, transdermal, parenteral, intravenous, intramuscular,intranasal, subcutaneous, regional (e.g., in the proximity of a tumor,particularly with the vasculature or adjacent vasculature of a tumor),percutaneous, intratracheal, intraperitoneal, intraarterial,intravesical, intratumoral, inhalation, perfusion, lavage, and oraladministration and formulation.

The term “intravascular” is understood to refer to delivery into thevasculature of a patient, meaning into, within, or in a vessel orvessels of the patient. In certain embodiments, the administration isinto a vessel considered to be a vein (intravenous), while in othersadministration is into a vessel considered to be an artery. Veinsinclude, but are not limited to, the internal jugular vein, a peripheralvein, a coronary vein, a hepatic vein, the portal vein, great saphenousvein, the pulmonary vein, superior vena cava, inferior vena cava, agastric vein, a splenic vein, inferior mesenteric vein, superiormesenteric vein, cephalic vein, and/or femoral vein. Arteries include,but are not limited to, coronary artery, pulmonary artery, brachialartery, internal carotid artery, aortic arch, femoral artery, peripheralartery, and/or ciliary artery. It is contemplated that delivery may bethrough or to an arteriole or capillary.

Intratumoral injection, or injection directly into the tumor vasculatureis specifically contemplated for discrete, solid, accessible tumors.Local, regional or systemic administration also may be appropriate. Fortumors of >4 cm, the volume to be administered will be about 4-10 ml(preferably 10 ml), while for tumors of <4 cm, a volume of about 1-3 mlwill be used (preferably 3 ml). Multiple injections delivered as singledose comprise about 0.1 to about 0.5 ml volumes. The viral particles mayadvantageously be contacted by administering multiple injections to thetumor, spaced at approximately 1 cm intervals. In the case of surgicalintervention, the present invention may be used preoperatively, torender an inoperable tumor subject to resection. Continuousadministration also may be applied where appropriate, for example, byimplanting a catheter into a tumor or into tumor vasculature. Suchcontinuous perfusion may take place for a period from about 1-2 hours,to about 2-6 hours, to about 6-12 hours, or about 12-24 hours followingthe initiation of treatment. Generally, the dose of the therapeuticcomposition via continuous perfusion will be equivalent to that given bya single or multiple injections, adjusted over a period of time duringwhich the perfusion occurs. It is further contemplated that limbperfusion may be used to administer therapeutic compositions of thepresent invention, particularly in the treatment of melanomas andsarcomas.

Treatment regimens may vary as well, and often depend on tumor type,tumor location, disease progression, and health and age of the patient.Obviously, certain types of tumor will require more aggressivetreatment, while at the same time, certain patients cannot tolerate moretaxing protocols. The clinician will be best suited to make suchdecisions based on the known efficacy and toxicity (if any) of thetherapeutic formulations.

In certain embodiments, the tumor being treated may not, at leastinitially, be resectable. Treatments with therapeutic viral constructsmay increase the resectability of the tumor due to shrinkage at themargins or by elimination of certain particularly invasive portions.Following treatments, resection may be possible. Additional treatmentssubsequent to resection will serve to eliminate microscopic residualdisease at the tumor site.

The treatments may include various “unit doses.” Unit dose is defined ascontaining a predetermined-quantity of the therapeutic composition. Thequantity to be administered, and the particular route and formulation,are within the skill of those in the clinical arts. A unit dose need notbe administered as a single injection but may comprise continuousinfusion over a set period of time. Unit dose of the present inventionmay conveniently be described in terms of plaque forming units (pfu) fora viral construct. Unit doses range from 10³, 10⁴, 10⁵, 10⁶, 10⁷, 10⁸,10⁹, 10¹⁰, 10¹¹, 10¹², 10¹³ pfu and higher. Alternatively, depending onthe kind of virus and the titer attainable, one will deliver 1 to 100,10 to 50, 100-1000, or up to about or at least about 1×10⁴, 1×10⁵,1×10⁶, 1×10⁷, 1×10⁸, 1×10⁹, 1×10¹⁰, 1×10¹¹, 1×10¹², 1×10¹³, 1×10¹⁴, or1×10¹⁵ or higher infectious viral particles (vp), including all valuesand ranges there between, to the tumor or tumor site.

B. Injectable Compositions and Formulations

The preferred method for the delivery of an expression construct orvirus encoding all or part of a poxvirus genome to cancer or tumor cellsin the present invention is via intratumoral injection. However, thepharmaceutical compositions disclosed herein may alternatively beadministered parenterally, intravenously, intradermally,intramuscularly, transdermally or even intraperitoneally as described inU.S. Pat. No. 5,543,158; U.S. Pat. No. 5,641,515 and U.S. Pat. No.5,399,363 (each specifically incorporated herein by reference in itsentirety).

Injection of nucleic acid constructs may be delivered by syringe or anyother method used for injection of a solution, as long as the expressionconstruct can pass through the particular gauge of needle required forinjection. A novel needleless injection system has recently beendescribed (U.S. Pat. No. 5,846,233) having a nozzle defining an ampulechamber for holding the solution and an energy device for pushing thesolution out of the nozzle to the site of delivery. A syringe system hasalso been described for use in gene therapy that permits multipleinjections of predetermined quantities of a solution precisely at anydepth (U.S. Pat. No. 5,846,225).

Solutions of the active compounds as free base or pharmacologicallyacceptable salts may be prepared in water suitably mixed with asurfactant, such as hydroxypropylcellulose. Dispersions may also beprepared in glycerol, liquid polyethylene glycols, and mixtures thereofand in oils. Under ordinary conditions of storage and use, thesepreparations contain a preservative to prevent the growth ofmicroorganisms. The pharmaceutical forms suitable for injectable useinclude sterile aqueous solutions or dispersions and sterile powders forthe extemporaneous preparation of sterile injectable solutions ordispersions (U.S. Pat. No. 5,466,468, specifically incorporated hereinby reference in its entirety). In all cases the form must be sterile andmust be fluid to the extent that easy syringability exists. It must bestable under the conditions of manufacture and storage and must bepreserved against the contaminating action of microorganisms, such asbacteria and fungi. The carrier can be a solvent or dispersion mediumcontaining, for example, water, ethanol, polyol (e.g., glycerol,propylene glycol, and liquid polyethylene glycol, and the like),suitable mixtures thereof, and/or vegetable oils. Proper fluidity may bemaintained, for example, by the use of a coating, such as lecithin, bythe maintenance of the required particle size in the case of dispersionand by the use of surfactants. The prevention of the action ofmicroorganisms can be brought about by various antibacterial andantifungal agents, for example, parabens, chlorobutanol, phenol, sorbicacid, thimerosal, and the like. In many cases, it will be preferable toinclude isotonic agents, for example, sugars or sodium chloride.Prolonged absorption of the injectable compositions can be brought aboutby the use in the compositions of agents delaying absorption, forexample, aluminum monostearate and gelatin.

For parenteral administration in an aqueous solution, for example, thesolution should be suitably buffered if necessary and the liquid diluentfirst rendered isotonic with sufficient saline or glucose. Theseparticular aqueous solutions are especially suitable for intravenous,intramuscular, subcutaneous, intratumoral and intraperitonealadministration. In this connection, sterile aqueous media that can beemployed will be known to those of skill in the art in light of thepresent disclosure. For example, one dosage may be dissolved in 1 ml ofisotonic NaCl solution and either added to 1000 ml of hypodermoclysisfluid or injected at the proposed site of infusion, (see for example,“Remington's Pharmaceutical Sciences” 15th Edition, pages 1035-1038 and1570-1580). Some variation in dosage will necessarily occur depending onthe condition of the subject being treated. The person responsible foradministration will, in any event, determine the appropriate dose forthe individual subject. Moreover, for human administration, preparationsshould meet sterility, pyrogenicity, general safety and purity standardsas required by FDA Office of Biologics standards.

Sterile injectable solutions are prepared by incorporating the activecompounds in the required amount in the appropriate solvent with variousof the other ingredients enumerated above, as required, followed byfiltered sterilization. Generally, dispersions are prepared byincorporating the various sterilized active ingredients into a sterilevehicle which contains the basic dispersion medium and the requiredother ingredients from those enumerated above. In the case of sterilepowders for the preparation of sterile injectable solutions, thepreferred methods of preparation are vacuum-drying and freeze-dryingtechniques which yield a powder of the active ingredient plus anyadditional desired ingredient from a previously sterile-filteredsolution thereof

The compositions disclosed herein may be formulated in a neutral or saltform. Pharmaceutically-acceptable salts, include the acid addition salts(formed with the free amino groups of the protein) and which are formedwith inorganic acids such as, for example, hydrochloric or phosphoricacids, or such organic acids as acetic, oxalic, tartaric, mandelic, andthe like. Salts formed with the free carboxyl groups can also be derivedfrom inorganic bases such as, for example, sodium, potassium, ammonium,calcium, or ferric hydroxides, and such organic bases as isopropylamine,trimethylamine, histidine, procaine and the like. Upon formulation,solutions will be administered in a manner compatible with the dosageformulation and in such amount as is therapeutically effective. Theformulations are easily administered in a variety of dosage forms suchas injectable solutions, drug release capsules and the like.

As used herein, “carrier” includes any and all solvents, dispersionmedia, vehicles, coatings, diluents, antibacterial and antifungalagents, isotonic and absorption delaying agents, buffers, carriersolutions, suspensions, colloids, and the like. The use of such mediaand agents for pharmaceutical active substances is well known in theart. Except insofar as any conventional media or agent is incompatiblewith the active ingredient, its use in the therapeutic compositions iscontemplated. Supplementary active ingredients can also be incorporatedinto the compositions.

The phrase “pharmaceutically-acceptable” or“pharmacologically-acceptable” refers to molecular entities andcompositions that do not produce an allergic or similar untowardreaction when administered to a human. The preparation of an aqueouscomposition that contains a protein as an active ingredient is wellunderstood in the art. Typically, such compositions are prepared asinjectables, either as liquid solutions or suspensions; solid formssuitable for solution in, or suspension in, liquid prior to injectioncan also be prepared.

C. Combination Treatments

The compounds and methods of the present invention may be used in thecontext of hyperproliferative diseases/conditions including cancer. Inorder to increase the effectiveness of a treatment with the compositionsof the present invention, such as a GM-CSF-expressing vaccinia virus, itmay be desirable to combine these compositions with other agentseffective in the treatment of those diseases and conditions. Forexample, the treatment of a cancer may be implemented with therapeuticcompounds of the present invention and other anti-cancer therapies, suchas anti-cancer agents or surgery.

Various combinations may be employed; for example, a poxvirus, such asvaccinia virus, is “A” and the secondary anti-cancer therapy is “B”:

A/B/A B/A/B B/B/A A/A/B A/B/B B/A/A A/B/B/BB/A/B/B B/B/B/A B/B/A/B A/A/B/B A/B/A/B A/B/B/AB/B/A/A B/A/B/A B/A/A/B A/A/A/B B/A/A/A A/B/A/A A/A/B/A

Administration of the poxvirus/vaccina vectors of the present inventionto a patient will follow general protocols for the administration ofthat particular secondary therapy, taking into account the toxicity, ifany, of the poxvirus treatment. It is expected that the treatment cycleswould be repeated as necessary. It also is contemplated that variousstandard therapies, as well as surgical intervention, may be applied incombination with the described cancer or tumor cell therapy.

An “anti-cancer” agent is capable of negatively affecting cancer in asubject, for example, by killing cancer cells, inducing apoptosis incancer cells, reducing the growth rate of cancer cells, reducing theincidence or number of metastases, reducing tumor size, inhibiting tumorgrowth, reducing the blood supply to a tumor or cancer cells, promotingan immune response against cancer cells or a tumor, preventing orinhibiting the progression of cancer, or increasing the lifespan of asubject with cancer. Anti-cancer agents include biological agents(biotherapy), chemotherapy agents, and radiotherapy agents. Moregenerally, these other compositions would be provided in a combinedamount effective to kill or inhibit proliferation of the cell. Thisprocess may involve contacting the cells with the expression constructand the agent(s) or multiple factor(s) at the same time. This may beachieved by contacting the cell with a single composition orpharmacological formulation that includes both agents, or by contactingthe cell with two distinct compositions or formulations, at the sametime, wherein one composition includes the expression construct and theother includes the second agent(s).

Tumor cell resistance to chemotherapy and radiotherapy agents representsa major problem in clinical oncology. One goal of current cancerresearch is to find ways to improve the efficacy of chemo- andradiotherapy by combining it with gene therapy. For example, the herpessimplex-thymidine kinase (HS-tK) gene, when delivered to brain tumors bya retroviral vector system, successfully induced susceptibility to theantiviral agent ganciclovir (Culver et al., 1992). In the context of thepresent invention, it is contemplated that poxvirus therapy could beused similarly in conjunction with chemotherapeutic, radiotherapeutic,immunotherapeutic or other biological intervention, in addition to otherpro-apoptotic or cell cycle regulating agents.

Alternatively, the poxviral therapy may precede or follow the otheragent treatment by intervals ranging from minutes to weeks. Inembodiments where the other agent and poxvirus are applied separately tothe cell, one would generally ensure that a significant period of timedid not expire between the time of each delivery, such that the agentand poxvirus would still be able to exert an advantageously combinedeffect on the cell. In such instances, it is contemplated that one maycontact the cell with both modalities within about 12-24 h of each otherand, more preferably, within about 6-12 h of each other. In somesituations, it may be desirable to extend the time period for treatmentsignificantly, however, where several days (2, 3, 4, 5, 6 or 7) toseveral weeks (1, 2, 3, 4, 5, 6, 7 or 8) lapse between the respectiveadministrations.

1. Chemotherapy

Cancer therapies also include a variety of combination therapies withboth chemical and radiation based treatments. Combination chemotherapiesinclude, for example, cisplatin (CDDP), carboplatin, procarbazine,mechlorethamine, cyclophosphamide, camptothecin, ifosfamide, melphalan,chlorambucil, busulfan, nitrosurea, dactinomycin, daunorubicin,doxorubicin, bleomycin, plicomycin, mitomycin, etoposide (VP16),tamoxifen, raloxifene, estrogen receptor binding agents, taxol,gemcitabien, navelbine, farnesyl-protein transferase inhibitors,transplatinum, 5-fluorouracil, vincristine, vinblastine andmethotrexate, Temazolomide (an aqueous form of DTIC), or any analog orderivative variant of the foregoing. The combination of chemotherapywith biological therapy is known as biochemotherapy.

2. Radiotherapy

Other factors that cause DNA damage and have been used extensivelyinclude what are commonly known as .gamma.-rays, X-rays, and/or thedirected delivery of radioisotopes to tumor cells. Other forms of DNAdamaging factors are also contemplated such as microwaves andUV-irradiation. It is most likely that all of these factors effect abroad range of damage on DNA, on the precursors of DNA, on thereplication and repair of DNA, and on the assembly and maintenance ofchromosomes. Dosage ranges for X-rays range from daily doses of 50 to200 roentgens for prolonged periods of time (3 to 4 wk), to single dosesof 2000 to 6000 roentgens. Dosage ranges for radioisotopes vary widely,and depend on the half-life of the isotope, the strength and type ofradiation emitted, and the uptake by the neoplastic cells.

The terms “contacted” and “exposed,” when applied to a cell, are usedherein to describe the process by which a therapeutic construct and achemotherapeutic or radiotherapeutic agent are delivered to a targetcell or are placed in direct juxtaposition with the target cell. Toachieve cell killing or stasis, both agents are delivered to a cell in acombined amount effective to kill the cell or prevent it from dividing.

3. Immunotherapy

Immunotherapeutics, generally, rely on the use of immune effector cellsand molecules to target and destroy cancer cells. The immune effectormay be, for example, an antibody specific for some marker on the surfaceof a tumor cell. The antibody alone may serve as an effector of therapyor it may recruit other cells to actually effect cell killing. Theantibody also may be conjugated to a drug or toxin (chemotherapeutic,radionuclide, ricin A chain, cholera toxin, pertussis toxin, etc.) andserve merely as a targeting agent. Alternatively, the effector may be alymphocyte carrying a surface molecule that interacts, either directlyor indirectly, with a tumor cell target. Various effector cells includecytotoxic T cells and NK cells. The combination of therapeuticmodalities, i.e., direct cytotoxic activity and inhibition or reductionof certain poxvirus polypeptides would provide therapeutic benefit inthe treatment of cancer.

Immunotherapy could also be used as part of a combined therapy. Thegeneral approach for combined therapy is discussed below. In one aspectof immunotherapy, the tumor cell must bear some marker that is amenableto targeting, i.e., is not present on the majority of other cells. Manytumor markers exist and any of these may be suitable for targeting inthe context of the present invention. Common tumor markers includecarcinoembryonic antigen, prostate specific antigen, urinary tumorassociated antigen, fetal antigen, tyrosinase (p97), gp68, TAG-72, HMFG,Sialyl Lewis Antigen, MucA, MucB, PLAP, estrogen receptor, lamininreceptor, erb B and p155. An alternative aspect of immunotherapy is toanticancer effects with immune stimulatory effects. Immune stimulatingmolecules also exist including: cytokines such as IL-2, IL4, IL-12,GM-CSF, IFN.gamma., chemokines such as MIP-1, MCP-1, IL-8 and growthfactors such as FLT3 ligand. Combining immune stimulating molecules,either as proteins or using gene delivery in combination with a tumorsuppressor such as mda-7 has been shown to enhance anti-tumor effects(Ju et al., 2000).

As discussed earlier, examples of immunotherapies currently underinvestigation or in use are immune adjuvants (e.g., Mycobacterium bovis,Plasmodium falciparum, dinitrochlorobenzene and aromatic compounds)(U.S. Pat. No. 5,801,005; U.S. Pat. No. 5,739,169; Hui and Hashimoto,1998; Christodoulides et al., 1998), cytokine therapy (e.g.interferons-α, -β and -γ; IL-1, GM-CSF and TNF) (Bukowski et al., 1998;Davidson et al., 1998; Hellstrand et al., 1998) gene therapy (e.g., TNF,IL-1, IL-2, p53) (Qin et al., 1998; Austin-Ward and Villaseca, 1998;U.S. Pat. No. 5,830,880 and U.S. Pat. No. 5,846,945) and monoclonalantibodies (e.g., anti-ganglioside GM2, anti-HER-2, anti-p185) (Pietraset al., 1998; Hanibuchi et al., 1998; U.S. Pat. No. 5,824,311).Herceptin (trastuzumab) is a chimeric (mouse-human) monoclonal antibodythat blocks the HER2-neu receptor. It possesses anti-tumor activity andhas been approved for use in the treatment of malignant tumors (Dillman,1999). Combination therapy of cancer with herceptin and chemotherapy hasbeen shown to be more effective than the individual therapies. Thus, itis contemplated that one or more anti-cancer therapies may be employedwith the poxvirus-related therapies described herein.

Passive Immunotherapy.

A number of different approaches for passive immunotherapy of cancerexist. They may be broadly categorized into the following: injection ofantibodies alone; injection of antibodies coupled to toxins orchemotherapeutic agents; injection of antibodies coupled to radioactiveisotopes; injection of anti-idiotype antibodies; and finally, purging oftumor cells in bone marrow.

Preferably, human monoclonal antibodies are employed in passiveimmunotherapy, as they produce few or no side effects in the patient.Humanized and chimeric monocolonal antibodies are also employedsuccessfully in cancer therapy. Monoclonal antibodies used as cancertherapeutics include edrecolomab, rituximab, trastuzumab, gemtuzumab,alemtuzumab, ibritumomab, tositumomab, cetuximab, bevacizumab,nimotuzumab, and panitumamab.

It may be favorable to administer more than one monoclonal antibodydirected against two different antigens or even antibodies with multipleantigen specificity. Treatment protocols also may include administrationof lympholines or other immune enhancers as described by Bajorin et al.(1988). The development of human monoclonal antibodies is described infurther detail elsewhere in the specification.

Active Immunotherapy.

In active immunotherapy, an antigenic peptide, polypeptide or protein,or an autologous or allogenic tumor cell composition or “vaccine” isadministered, generally with a distinct bacterial adjuvant (Ravindranathand Morton, 1991; Morton et al., 1992; Mitchell et al., 1990; Mitchellet al., 1993). In melanoma immunotherapy, those patients who elicit highIgM response often survive better than those who elicit no or low IgMantibodies (Morton et al., 1992). IgM antibodies are often transientantibodies and the exception to the rule appears to be anti-gangliosideor anticarbohydrate antibodies.

Adoptive Immunotherapy.

In adoptive immunotherapy, the patient's circulating lymphocytes, ortumor infiltrated lymphocytes, are isolated in vitro, activated bylymphokines such as IL-2 or transduced with genes for tumor necrosis,and readministered (Rosenberg et al., 1988; 1989). To achieve this, onewould administer to an animal, or human patient, an immunologicallyeffective amount of activated lymphocytes in combination with anadjuvant-incorporated antigenic peptide composition as described herein.The activated lymphocytes will most preferably be the patient's owncells that were earlier isolated from a blood or tumor sample andactivated (or “expanded”) in vitro. This form of immunotherapy hasproduced several cases of regression of melanoma and renal carcinoma,but the percentage of responders were few compared to those who did notrespond.

4. Genes

In yet another embodiment, the secondary treatment is a gene therapy inwhich a therapeutic polynucleotide is administered before, after, or atthe same time as an attenuated poxvirus is administered. Delivery of apoxvirus in conjunction with a vector encoding one of the following geneproducts will have a combined anti-cancer effect on target tissues.Alternatively, the poxvirus may be engineered as a viral vector toinclude the therapeutic polynucleotide. A variety of proteins areencompassed within the invention, some of which are described below.Table 2 lists various genes that may be targeted for gene therapy ofsome form in combination with the present invention.

Inducers of Cellular Proliferation.

The proteins that induce cellular proliferation further fall intovarious categories dependent on function. The commonality of all ofthese proteins is their ability to regulate cellular proliferation. Forexample, a form of PDGF, the sis oncogene, is a secreted growth factor.Oncogenes rarely arise from genes encoding growth factors, and at thepresent, sis is the only known naturally-occurring oncogenic growthfactor. In one embodiment of the present invention, it is contemplatedthat anti-sense mRNA directed to a particular inducer of cellularproliferation is used to prevent expression of the inducer of cellularproliferation.

The proteins FMS, ErbA, ErbB and neu are growth factor receptors.Mutations to these receptors result in loss of regulatable function. Forexample, a point mutation affecting the transmembrane domain of the Neureceptor protein results in the neu oncogene. The erbA oncogene isderived from the intracellular receptor for thyroid hormone. Themodified oncogenic ErbA receptor is believed to compete with theendogenous thyroid hormone receptor, causing uncontrolled growth.

The largest class of oncogenes includes the signal transducing proteins(e.g., Src, Abl and Ras). The protein Src is a cytoplasmicprotein-tyrosine kinase, and its transformation from proto-oncogene tooncogene in some cases, results via mutations at tyrosine residue 527.In contrast, transformation of GTPase protein ras from proto-oncogene tooncogene, in one example, results from a valine to glycine mutation atamino acid 12 in the sequence, reducing ras GTPase activity.

The proteins Jun, Fos and Myc are proteins that directly exert theireffects on nuclear functions as transcription factors.

Inhibitors of Cellular Proliferation.

The tumor suppressor oncogenes function to inhibit excessive cellularproliferation. The inactivation of these genes destroys their inhibitoryactivity, resulting in unregulated proliferation. The tumor suppressorsp53, p16 and C-CAM are described below.

In addition to p53, which has been described above, another inhibitor ofcellular proliferation is p16. The major transitions of the eukaryoticcell cycle are triggered by cyclin-dependent kinases, or CDK's. One CDK,cyclin-dependent kinase 4 (CDK4), regulates progression through the G₁.The activity of this enzyme may be to phosphorylate Rb at late G₁. Theactivity of CDK4 is controlled by an activating subunit, D-type cyclin,and by an inhibitory subunit, the p16^(INK4) has been biochemicallycharacterized as a protein that specifically binds to and inhibits CDK4,and thus may regulate Rb phosphorylation (Serrano et al., 1993; Serranoet al., 1995). Since the p16^(INK4) protein is a CDK4 inhibitor(Serrano, 1993), deletion of this gene may increase the activity ofCDK4, resulting in hyperphosphorylation of the Rb protein. p16 also isknown to regulate the function of CDK6.

p16^(INK4) belongs to a newly described class of CDK-inhibitory proteinsthat also includes p16_(B), p19, p21, WAF1, and p27^(KIP1). Thep16^(INK4) gene maps to 9p21, a chromosome region frequently deleted inmany tumor types. Homozygous deletions and mutations of the p16^(INK4)gene are frequent in human tumor cell lines. This evidence suggests thatthe p16^(INK4) gene is a tumor suppressor gene. This interpretation hasbeen challenged, however, by the observation that the frequency of thep16^(INK4) gene alterations is much lower in primary uncultured tumorsthan in cultured cell lines (Caldas et al., 1994; Cheng et al., 1994;Hussussian et al., 1994; Kamb et al., 1994; Kamb et al., 1994; Mori etal., 1994; Okamoto et al., 1994; Nobori et al., 1994; Orlow et al.,1994; Arap et al., 1995). Restoration of wild-type p16^(INK4) functionby transfection with a plasmid expression vector reduced colonyformation by some human cancer cell lines (Okamoto, 1994; Arap, 1995).

Other genes that may be employed according to the present inventioninclude Rb, APC, DCC, NF-1, NF-2, WT-1, MEN-I, MEN-II, zac1, p73, VHL,MMAC1/PTEN, DBCCR-1, FCC, rsk-3, p27, p27/p16 fusions, p21/p27 fusions,anti-thrombotic genes (e.g., COX-1, TFPI), PGS, Dp, E2F, ras, myc, neu,raf erb, fms, trk, ret, gsp, hst, abl, E1A, p300, genes involved inangiogenesis (e.g., VEGF, FGF, thrombospondin, BAI-1, GDAIF, or theirreceptors) and MCC.

Regulators of Programmed Cell Death.

Apoptosis, or programmed cell death, is an essential process for normalembryonic development, maintaining homeostasis in adult tissues, andsuppressing carcinogenesis (Kerr et al., 1972). The Bcl-2 family ofproteins and ICE-like proteases have been demonstrated to be importantregulators and effectors of apoptosis in other systems. The Bcl-2protein, discovered in association with follicular lymphoma, plays aprominent role in controlling apoptosis and enhancing cell survival inresponse to diverse apoptotic stimuli (Bakhshi et al., 1985; Cleary andSklar, 1985; Cleary et al., 1986; Tsujimoto et al., 1985; Tsujimoto andCroce, 1986). The evolutionarily conserved Bcl-2 protein now isrecognized to be a member of a family of related proteins, which can becategorized as death agonists or death antagonists.

Subsequent to its discovery, it was shown that Bcl-2 acts to suppresscell death triggered by a variety of stimuli. Also, it now is apparentthat there is a family of Bcl-2 cell death regulatory proteins whichshare in common structural and sequence homologies. These differentfamily members have been shown to either possess similar functions toBcl-2 (e.g., BCl_(XL), Bcl_(w), Bcl_(s), Mcl-1, Al, Bfl-1) or counteractBcl-2 function and promote cell death (e.g., Bax, Bak, Bik, Bim, Bid,Bad, Haraliri).

5. Surgery

Approximately 60% of persons with cancer will undergo surgery of sometype, which includes preventative, diagnostic or staging, curative andpalliative surgery. Curative surgery is a cancer treatment that may beused in conjunction with other therapies, such as the treatment of thepresent invention, chemotherapy, radiotherapy, hormonal therapy, genetherapy, immunotherapy and/or alternative therapies.

Curative surgery includes resection in which all or part of canceroustissue is physically removed, excised, and/or destroyed. Tumor resectionrefers to physical removal of at least part of a tumor. In addition totumor resection, treatment by surgery includes laser surgery,cryosurgery, electrosurgery, and microscopically controlled surgery(Mohs' surgery). It is further contemplated that the present inventionmay be used in conjunction with removal of superficial cancers,precancers, or incidental amounts of normal tissue.

Upon excision of part of all of cancerous cells, tissue, or tumor, acavity may be formed in the body. Treatment may be accomplished byperfusion, direct injection or local application of the area with anadditional anti-cancer therapy. Such treatment may be repeated, forexample, every 1, 2, 3, 4, 5, 6, or 7 days, or every 1, 2, 3, 4, and 5weeks or every 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, or 12 months. Thesetreatments may be of varying dosages as well.

6. Other Agents

It is contemplated that other agents may be used in combination with thepresent invention to improve the therapeutic efficacy of treatment.These additional agents include immunomodulatory agents, agents thataffect the upregulation of cell surface receptors and GAP junctions,cytostatic and differentiation agents, inhibitors of cell adehesion,agents that increase the sensitivity of the hyperproliferative cells toapoptotic inducers, or other biological agents. Immunomodulatory agentsinclude tumor necrosis factor; interferon-α, -β, and -γ; IL-2 and othercytokines; F42K and other cytokine analogs; or MIP-1, MIP-1.beta.,MCP-1, RANTES, and other chemolines. It is further contemplated that theupregulation of cell surface receptors or their ligands such as Fas/Fasligand, DR4 or DR5/TRAIL (Apo-2 ligand) would potentiate the apoptoticinducing abililties of the present invention by establishment of anautocrine or paracrine effect on hyperproliferative cells. Increasesintercellular signaling by elevating the number of GAP junctions wouldincrease the anti-hyperproliferative effects on the neighboringhyperproliferative cell population. In other embodiments, cytostatic ordifferentiation agents can be used in combination with the presentinvention to improve the anti-hyerproliferative efficacy of thetreatment Inhibitors of cell adehesion are contemplated to improve theefficacy of the present invention. Examples of cell adhesion inhibitorsare focal adhesion kinase (FAKs) inhibitors and Lovastatin. It isfurther contemplated that other agents that increase the sensitivity ofa hyperproliferative cell to apoptosis, such as the antibody c225, couldbe used in combination with the present invention to improve thetreatment efficacy.

Apo2 ligand (Apo2L, also called TRAIL) is a member of the tumor necrosisfactor (TNF) cytokine family. TRAIL activates rapid apoptosis in manytypes of cancer cells, yet is not toxic to normal cells. TRAIL mRNAoccurs in a wide variety of tissues. Most normal cells appear to beresistant to TRAIL's cytotoxic action, suggesting the existence ofmechanisms that can protect against apoptosis induction by TRAIL. Thefirst receptor described for TRAIL, called death receptor 4 (DR4),contains a cytoplasmic “death domain”; DR4 transmits the apoptosissignal carried by TRAIL. Additional receptors have been identified thatbind to TRAIL. One receptor, called DR5, contains a cytoplasmic deathdomain and signals apoptosis much like DR4. The DR4 and DR5 mRNAs areexpressed in many normal tissues and tumor cell lines. Recently, decoyreceptors such as DcR1 and DcR2 have been identified that prevent TRAILfrom inducing apoptosis through DR4 and DR5. These decoy receptors thusrepresent a novel mechanism for regulating sensitivity to apro-apoptotic cytokine directly at the cell's surface. The preferentialexpression of these inhibitory receptors in normal tissues suggests thatTRAIL may be useful as an anticancer agent that induces apoptosis incancer cells while sparing normal cells. (Marsters et al., 1999).

There have been many advances in the therapy of cancer following theintroduction of cytotoxic chemotherapeutic drugs. However, one of theconsequences of chemotherapy is the development/acquisition ofdrug-resistant phenotypes and the development of multiple drugresistance. The development of drug resistance remains a major obstaclein the treatment of such tumors and therefore, there is an obvious needfor alternative approaches such as gene therapy.

Another form of therapy for use in conjunction with chemotherapy,radiation therapy or biological therapy includes hyperthermia, which isa procedure in which a patient's tissue is exposed to high temperatures(up to 106° F.). External or internal heating devices may be involved inthe application of local, regional, or whole-body hyperthermia. Localhyperthermia involves the application of heat to a small area, such as atumor. Heat may be generated externally with high-frequency wavestargeting a tumor from a device outside the body. Internal heat mayinvolve a sterile probe, including thin, heated wires or hollow tubesfilled with warm water, implanted microwave antennae, or radiofrequencyelectrodes.

A patient's organ or a limb is heated for regional therapy, which isaccomplished using devices that produce high energy, such as magnets.Alternatively, some of the patient's blood may be removed and heatedbefore being perfused into an area that will be internally heated.Whole-body heating may also be implemented in cases where cancer hasspread throughout the body. Warm-water blankets, hot wax, inductivecoils, and thermal chambers may be used for this purpose.

Hormonal therapy may also be used in conjunction with the presentinvention or in combination with any other cancer therapy previouslydescribed. The use of hormones may be employed in the treatment ofcertain cancers such as breast, prostate, ovarian, or cervical cancer tolower the level or block the effects of certain hormones such astestosterone or estrogen. This treatment is often used in combinationwith at least one other cancer therapy as a treatment option or toreduce the risk of metastases.

TABLE 2 Oncogenes Gene Source Human Disease Function Growth FactorsHST/KS Transfection FGF family member INT-2 MMTV promoter FGF familymember Insertion INTI/WNTI MMTV promoter Factor-like Insertion SISSimian sarcoma virus PDGF B Receptor Tyrosine Kinases ERBB/HER Avianerythroblastosis Amplified, deleted EGF/TGF-α/ virus; ALV promoterSquamous cell Amphiregulin/ insertion; amplified Cancer; glioblastomaHetacellulin receptor human tumors ERBB-2/NEU/HER-2 Transfected from ratAmplified breast, Regulated by NDF/ Glioblastomas Ovarian, gastricHeregulin and EGF- cancers Related factors FMS SM feline sarcoma virusCSF-1 receptor KIT HZ feline sarcoma virus MGF/Steel receptorHematopoieis TRK Transfection from NGF (nerve growth human colon cancerFactor) receptor MET Transfection from Scatter factor/HGF humanosteosarcoma Receptor RET Translocations and Sporadic thyroid cancer;Orphan receptor Tyr point mutations Familial medullary Kinase thyroidcancer; multiple endocrine neoplasias 2A and 2B ROS URII avian sarcomaOrphan receptor Tyr Virus Kinase PDGF receptor Translocation ChronicTEL(ETS-like Myelomonocytic Transcription factor)/ Leukemia PDGFreceptor gene Fusion TGF-β receptor Colon carcinoma Mismatch mutationtarget NONRECEPTOR TYROSINE KINASES ABI. Abelson Mul.V Chronicmyelogenous Interact with RB, RNA Leukemia translocation Polymerase,CRK, with BCR CBL FPS/FES Avian Fujinami SV; GA FeSV LCK Mul.V (murineSrc family; T cell leukemia Signaling; interacts virus) promoter CD4/CD8T cells insertion SRC Avian Rous sarcoma Membrane-associated Virus Tyrkinase with signaling function; activated by receptor kinases YES AvianY73 virus Src family; signaling SER/THR PROTEIN KINASES AKT AKT8 murineretrovirus Regulated by PI(3)K?; regulate 70-kd S6 k? MOS Maloney murineSV GVBD; cystostatic factor; MAP kinase kinase PIM-1 Promoter insertionMouse RAF/MIL 3611 murine SV; MH2 Signaling in RAS avian SV PathwayMISCELLANEOUS CELL SURFACE APC Tumor suppressor Colon cancer Interactswith catenins DCC Tumor suppressor Colon cancer CAM domains E-cadherinCandidate tumor Breast cancer Extracellular homotypic Suppressorbinding; intracellular interacts with catenins PTC/NBCCS Tumorsuppressor and Nevoid basal cell cancer 12 transmembrane Drosophilahomology Syndrome (Gorline domain; signals syndrome) through Gli homogueCI to antagonize Hedgehog pathway TAN-1 Notch Translocation T-ALI.Signaling homologue MISCELLANEOUS SIGNALING BCL-2 Translocation B-celllymphoma Apoptosis CBL Mu Cas NS-1 V Tyrosine- Phosphorylated RINGfinger interact Abl CRK CT1010 ASV Adapted SH2/SH3 interact Abl DPC4Tumor suppressor Pancreatic cancer TGF-β-related signaling Pathway MASTransfection and Possible angiotensin Tumorigenicity Receptor NCKAdaptor SH2/SH3 GUANINE NUCLEOTIDE EXCHANGERS AND BINDING PROTEINS BCRTranslocated with ABL Exchanger; protein in CML Kinase DBL TransfectionExchanger GSP NF-1 Hereditary tumor Tumor suppressor RAS GAP SuppressorNeurofibromatosis OST Transfection Exchanger Harvey-Kirsten, N- HaRatSV; Ki RaSV; Point mutations in many Signal cascade RAS Balb-MoMuSV;human tumors Transfection VAV Transfection S112/S113; exchanger NUCLEARPROTEINS AND TRANSCRIPTION FACTORS BRCA1 Heritable suppressor MammaryLocalization unsettled Cancer/ovarian cancer BRCA2 Heritable suppressorMammary cancer Function unknown ERBA Avian erythroblastosis Thyroidhormone Virus receptor (transcription) ETS Avian E26 virus DNA bindingEVII MuLV promotor AML Transcription factor Insertion FOS FBI/FBR murineTranscription factor osteosarcoma viruses with c-JUN GLI Amplifiedglioma Glioma Zinc finger; cubitus Interruptus homologue is in hedgehogsignaling pathway; inhibitory link PTC and hedgehog HMGI /LIMTranslocation t(3:12) Lipoma Gene fusions high t(12:15) mobility groupHMGI-C (XT-hook) and transcription factor LIM or acidic domain JUNASV-17 Transcription factor AP-1 with FOS MLL/VHRX +Translocation/fusion Acute myeloid leukemia Gene fusion of DNA- ELI/MENELL with MLL binding and methyl Trithorax-like gene transferase MLL withELI RNA pol II Elongation factor MYB Avian myeloblastosis DNA bindingVirus MYC Avian MC29; Burkitt's lymphoma DNA binding with TranslocationB-cell MAX partner; cyclin Lymphomas; promoter Regulation; interactInsertion avian RB?; regulate leukosis Apoptosis? Virus N-MYC AmplifiedNeuroblastoma L-MYC Lung cancer REL Avian NF-κB familyRetriculoendotheliosis Transcription factor Virus SKI Avian SKV770Transcription factor Retrovirus VHL Heritable suppressor VonHippel-Landau Negative regulator or Syndrome elongin; transcriptionalelongation complex WT-1 Wilm's tumor Transcription factor CELL CYCLE/DNADAMAGE RESPONSE ATM Hereditary disorder Ataxia-telangiectasiaProtein/lipid kinase Homology; DNA damage response upstream in P53pathway BCL-2 Translocation Follicular lymphoma Apoptosis FACC Pointmutation Fanconi's anemia group C (predisposition Leukemia FHIT Fragilesite 3p14.2 Lung carcinoma Histidine triad-related Diadenosine 5′,3″″-P¹ · p⁴ tetraphosphate Asymmetric hydrolase hMLI/MutL HNPCC Mismatchrepair; MutL Homologue HMSH2/MutS HNPCC Mismatch repair; MutS HomologueHPMS1 HNPCC Mismatch repair; MutL Homologue hPMS2 HNPCC Mismatch repair;MutL Homologue INK4/MTS1 Adjacent INK-4B at Candidate MTS1 p16 CDKinhibitor 9p21; CDK Suppressor and MLM complexes melanoma geneINK4B/MTS2 Candidate suppressor p15 CDK inhibitor MDM-2 AmplifiedSarcoma Negative regulator p53 p53 Association with SV40 Mutated > 50%human Transcription factor; T antigen Tumors, including Checkpointcontrol; hereditary Li-Fraumeni apoptosis syndrome PRAD1/BCL1Translocation with Parathyroid adenoma; Cyclin D Parathyroid hormoneB-CLL or IgG RB Hereditary Retinoblastoma; Interact cyclin/cdk;Retinoblastoma; Osteosarcoma; breast regulate E2F Association with manyCancer; other sporadic transcription factor DNA virus tumor CancersAntigens XPA Xeroderma Excision repair; photo- Pigmentosum; skin productrecognition; Cancer predisposition zinc finger

V. Examples

The following examples are given for the purpose of illustrating variousembodiments of the invention and are not meant to limit the presentinvention in any fashion. One skilled in the art will appreciate readilythat the present invention is well adapted to carry out the objects andobtain the ends and advantages mentioned, as well as those objects, endsand advantages inherent herein. The present examples, along with themethods described herein are presently representative of preferredembodiments, are exemplary, and are not intended as limitations on thescope of the invention. Changes therein and other uses which areencompassed within the spirit of the invention as defined by the scopeof the claims will occur to those skilled in the art.

Example 1 Material and Methods

Viruses and Cell Lines.

The panel of wild type poxvirus strains (Wyeth, Western Reserve (WR),USSR, Tian Tan, Tash Kent, Patwadangar, Lister, King, IHD-W, IHD-J andEvans) was kindly provided by Dr Geoff Smith, Imperial College, London.Human Adenovirus serotype 5 (Ad5) was obtained from ATCC. The Viralgrowth factor (VGF) deleted strain of WR (vSC20) was kindly provided byDr Bernie Moss, NIH. The thymidine kinase deleted strain of WR (vJS6)and the TK-, VGF-double deleted strain of WR (vvDD) are described inPuhlmann et al. (2000) and McCart et al. (2001). WR strain expressingfirefly luciferase was kindly provided by Dr Gary Luker, (Uni Michigan).

Vaccinia strain JX-963 was constructed by recombination of a version ofthe pSC65 plasmid containing the E. coli gpt and human GM-CSF genes(under the control of the p7.5 and pSE/L promoters respectively) intothe thymidine kinase gene of the vSC20 (VGF deleted) strain of WR.Further selection of white plaques after propagation of the virus inX-Gal produced a virus with non-functioning lacZ (lacZ is expressed fromwithin VGF in vSC20). Correct insertion into the TK gene and loss oflacZ function was verified by sequencing and GM-CSF production verifiedby ELISA.

The vvDD expressing luciferase was constructed by insertion of a versionof the pSC65 plasmid with luciferase under control of the p7.5 promoterinto vSC20. Bioluminescence was verified using an IVIS 50 system(Xenogen, Alameda).

The human tumor cell lines include A2780 (Ovarian, obtained from ECACC),A549 (lung, obtained from ECACC), HCT 116, HT-29 and SW620 (colon,obtained from ATCC), HT-1080 (fibrosarcoma, obtained from ATCC), LNCaP(prostate, obtained from ATCC), PANC-1 (pancreatic, obtained from ATCC),MCF-7 (breast, obtained from ATCC). Non-transformed cells include MRC-5(lung fibroblast, obtained from ATCC), Beas-2B (bronchial epithelial,kindly provided by Tony Reid, UCSD) and the primary, normal cells NHBE(Normal human bronchial epithelial) and SAEC (Small airway bronchialepithelial), both obtained from Clonetics (Walkersville, Md.).

The mouse tumor cell lines include CMT 64 (C57/B6 lung, obtained fromCancer Research UK), JC (BALB/c mammary, obtained from ATCC), MC38(C57/B6 colon, obtained from NIH) and TIB-75 (BNL 1ME A.7R.1)(BALB/chepatic, obtained from ATCC). The cell lines NIH 3T3 and NIH 3T3overexpressing H-Ras were kindly provided by Richard Marais (ICR,London). The rabbit tumor cell line VX2 has been described previously(Kidd, 1940; Tjernberg, 1962; Chen et al., 2004).

In vitro replication and cytopathic effect assays. Cell lines are seededinto 6-well plates at 5×10⁶ cells/well and left overnight. Virus wasthen added at a multiplicity of infection (MOI) of 1.0 Plaque formingunits (PFU)/cell and allowed to infect for 2 h. At the end of theinfection the media was changed and plates incubated for 48 h, the cellswere then scraped into the media and collected. Cells were lysed bythree rounds of freezing and thawing followed by sonication beforeserial dilutions of the crude viral lysate was added to BSC-1 cells totiter the virus. Plaque assay was performed as described previously(Earl et al., 1998). Adenovirus was titered on A549 cells (Earl et al.,1998). Studies are typically run in triplicate.

In order to assess the cytopathic effect (CPE) of the virus, cells wereseeded at 1000 cells/well in 96-well plates and allowed to attachovernight. Serial dilutions of the viruses to be tested were then addedto the plates in triplicate (MOI range from 100 to 0.001) and the platesincubated for a further 72 h. After this time media was replaced withmedia without serum and MTS (Promega) added to the plates. After 2-4 hincubation the absorbance at 450 nm was read on an ELISA plate reader.Cytopathic effect was determined as reduction in viability of a testwell relative to both untreated wells containing cells only (100%viable) and cell-free wells (0% viable). Results were represented as theMOI at which 50% of the cell layer was viable (effective concentration50%, EC50).

Mouse Syngeneic and Xenograft Tumor Model Studies.

Immunocompetent mice are implanted subcutaneously with syngeneic tumorcells (1×10⁶ cells/mouse), such that JC and TIB-75 cells are implantedinto BALB/c mice and MC38 and CMT 64 cells are implanted into C57/B6mice. Certain human xenograft models involve 1×10⁷ HT29 cells implantedsubcutaneously into SCID mice (all mice are aged 8-10 weeks and sexmatched). Once tumors reached 50-100 mm³ animals are regrouped andtreated as indicated. Tumor sizes were followed by caliper measurement.

Mice treated with luciferase expressing virus can be imaged using anIVIS 100 system (Xenogen, Alameda). Mice are injected intraperitoneallywith luciferin (30 mg/kg) and anesthetized (2% isoflurane) prior toimaging.

Some mice are sacrificed at times indicated post-treatment and organsare recovered for viral biodistribution or immunohistochemical studies.For viral biodistribution, organs are snap frozen and ground beforeplaque assays are performed as described. For immunohistochemistrystudies, organs are fixed in formalin before embedding in paraffinblocks for sectioning. Sections are stained with hematoxylin and eosin(H & E) and with viral coat proteins (polyclonal anti-vaccinia antibodyor polyclonal antihexon antibody for adenovirus treated animals).

Rabbit Model.

The implantation of VX2 tumors into the livers of New Zealand Whiterabbits and the measurement of tumor progression and metastasis to thelungs by CT and ultrasound scans has been described previously (Paeng etal., 2003).

Cytotoxic T-Lymphocyte (CTL) Assay.

This is performed by mixing labeled peripheral blood lymphocytes (PBLs)obtained from rabbits treated as indicated with VX2 tumor cells. After a4 h period cell apoptosis was measured by propidium iodide staining andflow cytometry.

Neutralizing Antibody Assay.

Production of anti-vaccinia neutralizing antibody is measured in theplasma obtained from rabbits post-treatment. Dilutions of plasma aremixed with 1000 PFU of vaccinia overnight before addition to a 96-wellplate containing A2780 cells. After 72 h cell viability is measured byMTS assay. Viral neutralization is measured as the dilution of plasmarequired to prevent viral inactivation.

Statistical Analyses.

Kaplan-Meier curves are compared using the Generalized Wilcoxin test.Tumor response rates and metastasis-free rates are typically comparedwith Fisher's exact test.

Example 2 Rat Tumor Model

Rats (Sprague-Dawley, Males) were exposed to carcinogen(N-Nitrosomorpholine, NNM) in their drinking water (175 mg/L) for aperiod of 8 weeks, during which time liver cirrhosis developed, followedby in situ development of tumors (hepatocellular carcinoma orcholangiocarcinoma) within the liver between weeks 16-20 on average(model previously described in Oh et al., 2002). Tumor detection andevaluation was performed by an experienced ultrasonographer usingultrasound imaging. Tumor sizes were approximately 0.75-1.5 cm. indiameter at baseline immediately prior to treatment initiation; tumorvolumes were not significantly different at baseline between the controland treatment groups (estimated mean volumes were 400-500 mm³). Controlanimals (n=17) received no treatment, whereas treated animals (n=6)received intravenous injections (via tail vein) with a poxvirus (Wyethstrain; thymidine kinase gene deletion present) expressing human GM-CSFfrom a synthetic early-late promoter (virus construct described inMastrangelo et al., 1999). Virus was administered at a dose of 10⁸plaque-forming units (titered as in Earl et al., 1998) in a total volumeof 0.75 ml; (virus suspension mixed with 10 mM Tris up to the desiredvolume) intravenously by tail vein over 60 seconds. Treatment wasrepeated every two weeks for three total doses (day 1, 15 and 29).

Over ten weeks following the initiation of treatment, the control tumorsincreased in size significantly until reaching a mean of approximately3000 mm³ (S.E. 500) (FIG. 1). Control animals needed to be sacrificedfor ethical reasons due to tumor progression at this time. All tumorshad increased in size significantly. In contrast, five of the sixtreated tumors regressed completely (below the limit of detection byultrasound). The mean tumor volume in the treated group wasapproximately 50 mm³ (S.E., <10; p<0.01 vs. controls).

Example 3 Rabbit VX2 Tumor Model

A study was performed in a VX2 rabbit carcinoma model (as described inPaeng et al., 2003). Rabbit was selected as a species because humanGM-CSF was previously demonstrated to have significant biologicalactivity in rabbits (in contrast to mice). VX2 tumors were grown inmuscle of New Zealand white rabbits and cells from a 1-2 mm³ fragment oftumor were dissociated, resuspended in 0.1 ml normal saline and wereinjected beneath the liver capsule (21 gauge needle; injection sitecovered with surgical patch with a purse-string tie) and allowed to growfor 14 days until primary tumors were established (mean diameter,1.5-2.0 cm; est. volume 2-4 cm³). VX2 cells were demonstrated to beinfectable by vaccinia poxvirus ex vivo in a standard burst assay. Tumorsizes were monitored over time by CT scanning and by ultrasound. Overthe following seven weeks, control (untreated) animals (n=18) developedtumor progression within the liver, with estimated mean tumor volumesreaching approximately 100 cm³ (S.E. approximately 20). In addition,numerous tumor metastases progressed and became detectable within thelungs and livers over time (FIGS. 2A-B). By week 7, control animals allhad detectable metastases, with a mean number of lung metastases of 17(S.E. 2.3). The median survival of these control animals was 55 days(post-treatment initiation in treated animals), and all were dead within80 days.

Treated animals (n=3) in the first experiment received a singleintravenous injection (via tail vein) with a poxvirus (Wyeth strain;thymidine kinase gene deletion present) expressing human GM-CSF from asynthetic early-late promoter (virus construct described in Mastrangeloet at, 1999). Virus was administered at a dose of 10⁹ plaque-formingunits (titered as in Earl et al., 1998) in a total volume of 7 ml;(virus suspension mixed with 10 mM Tris up to the desired volume)intravenously by ear vein over 60 seconds. By week seven, in contrast tocontrols, treated animals had no lung metastases detectable by CTscanning (FIGS. 2A-2B). Survival was significantly increased, also. By110 days post-treatment initiation, the median survival had not beenreached, and approximately 70% were still alive.

Treated animals (n=6 per group) in a second experiment received threeweekly intravenous injections (via tail vein) with either JX-594, apoxvirus (Wyeth strain; thymidine kinase gene deletion present)expressing human GM-CSF from a synthetic early-late promoter (virusconstruct described in Mastrangelo et al., 1999, which is herebyincorporated by reference), vvDD, a vaccinia WR strain with deletions inthymidine kinase and vaccinia growth factor genes (vvDD as described byMcCart et al., 1999), or JX-963, vaccinia WR strain with deletions inthymidine kinase and vaccinia growth factor genes and expressing humanGM-CSF from a synthetic early-late promoter. Virus was administered at adose of 10⁸ plaque-forming units (titered as in Earl et al., 1998) in atotal volume of 7 ml; (virus suspension mixed with 10 mM Tris up to thedesired volume) intravenously by ear vein over 60 seconds. By weekseven, in contrast to controls, JX-963 treated animals had no lungmetastases detectable by CT scanning (p<0.01 vs. controls) (FIG. 4).JX-594-treated animals had a mean of 8 lung tumors (S.E. 2; p<0.05 vscontrols). vvDD-treated animals had a mean of 5 lung tumors (S.E. 2;p<0.05 vs controls). Of note, JX-963 and vvDD also had significantefficacy against the primary tumor growth in the liver, in contrast toJX-594 at this dose (FIG. 3) and JX-963 dramatically increased thesurvival of these animals (FIG. 5).

The GM-CSF-expressing virus JX-963 had significantly better efficacyagainst both primary tumors and lung metastases than itsnon-GM-CSF-expressing control vvDD; 2) the GM-CSF-expressing virusJX-963 had significantly better efficacy against both primary tumors andlung metastases than its GM-CSF-expressing Wyeth strain control (despitean additional deletion in the vgf gene not present in JX-594).Therefore, intravenous administration with a vaccinia expressing humanGM-CSF resulted in significantly better efficacy over the same vacciniawithout GM-CSF, and intravascular administration of a WR strain deletionmutant expressing human GM-CSF was significantly better than a Wyethstrain (standard vaccine strain) deletion mutant expressing GM-CSF.

Example 4 Systemic Cancer Efficacy with JX-963

Targeted therapies hold great promise for the treatment of cancer, butnovel agents are still needed as resistance frequently develops throughmutation of the target molecules and/or tumor escape through pathwayredundancies. Oncolytic viruses are viruses that have their replicationrestricted to malignant cell types, either inherently or through geneticengineering (Thorne et al., 2005). Selective intratumoral replicationleads to virus multiplication, killing of the infected cancer cell byunique and apoptosis-independent mechanisms (oncolysis) and spread ofthe virus to other tumor cells. Virotherapeutics therefore have thepotential to effectively treat refractory cancers and clinicalproof-of-concept has been achieved with local or regional administrationfor several oncolytic viruses (Parato et al., 2005)². However, foroncolytic viruses to have a major impact on patient survival, systemicefficacy and intravenous delivery will be needed.

The inventor has therefore undertaken a stepwise design and developmentstrategy to create a more effective systemic agent. First, the inventoridentified poxviruses such as vaccinia as a virus species that hasevolved for systemic dissemination and resistance to clearance bycomplement and antibodies (Smith et al., 1997; Buller and Palumbo,1991). Vaccinia has well-defined mechanisms to allow for transport inthe blood without inactivation and can spread rapidly within tissues, italso has a long history of human use during the smallpox eradicationcampaign. A panel of vaccinia viruses used during the vaccinationprogram, and some related strains were screened for their ability toreplicate in normal (NHBE) and tumor (A2780) cells. All vaccinia strainsreplicated to higher levels in the tumor cell line than in the normalcells (FIG. 6A), but the therapeutic index (tumor to normal cellreplication ratio) varied between strains. Strains used extensively inthe laboratory (such as Western Reserve (WR)) tended to display greaterinherent tumor selectivity in vitro than their parental vaccine strains(Wyeth). This is the first time that wild type vaccinia strains havebeen shown to display inherent superior replication in tumor cell linesrelative to normal cells. This is not true for all viruses however, asAdenovirus serotype 5 (Ad5) (the backbone for the majority of oncolyticviruses in the clinic) did not display such selectivity (FIG. 10A).

Another desirable attribute for an oncolytic agent is rapid intratumoralspread (Wein et al., 2003). This can be achieved through a shortreplication cycle and early release of virus from infected cells. Theability of the WR strain of vaccinia to destroy tumor cells wastherefore examined at early time points (72 h) after infection andcompared to Ad5 and the oncolytic adenovirus strain dl1520 (ONYX-015)(Heise et al., 1997) (FIG. 6B). WR displayed up to 5-logs of increasedkilling potential in tumor cells at this time relative to both Ad5 anddl1520, as well as greater tumor selectivity than either adenoviralstrain.

The major limitation of most oncolytic viruses tested to date is aninability to efficiently infect tumors following systemic delivery, asseen when 1×10⁹ plaque forming units (PFU) of Ad5 were deliveredintravenously to subcutaneous tumor models in mice (FIG. 6C and FIG.10B); this equates to a dose of 3.5×10¹² PFU in a 70 kg human, higherthan ever given to a patient. Little or no replicating virus was evidentin tumors (as detected by immunohistochemical staining for viral coatproteins 48 and 72 h after viral delivery). Vaccinia strain WR howevercould effectively traffic to and infect the tumors in these same models,with up to 50% of the tumor cells staining positive within 48 h oftreatment. Furthermore, vaccinia was able to persist in the tumor for atleast 10 days (FIG. 10B), despite the fact an immune response would havebeen initiated by this time.

In order to maximize safety, particularly for intravenous administrationin immunodeficient cancer patients, attenuating and tumor-targetinggenetic deletions were introduced into the virus. The inventor haspreviously described preferential tumor-expression of viral genes withinsertions into the vaccinia thymidine kinase (TK) gene and of TK andviral growth factor (VGF) double deletions (Puhlmann et al., 1999;McCart et al., 2001). Although the targeting mechanisms of thesedeletions were not previously demonstrated, the rationale was torestrict virus replication and oncolysis to cancer cells with elevatedE2F levels (as E2F drives production of the cellular thymidine kinasegene product (Hengstschlager et al. 1994)) and activation of theepidermal growth factor (EGF) receptor pathway (as activation of thispathway by VGF is necessary for efficient viral replication (Andrade etal., 2004)). Here it is shown that the TK and VGF double deleted virus(vvDD) displayed an impressive ability to destroy a wide range of tumorcells of different origins (FIG. 7). It was also found that singledeletions in either the vaccinia TK or the VGF genes attenuated theability of vaccinia to replicate in non-proliferating, non-transformedhuman cell lines, while the double deleted virus (vvDD) was furtherattenuated (FIG. 11). None of these strains were attenuated in theirability to replicate in human tumor cells.

It was further found that the block in the ability of the VGF-deletedvirus to replicate in non-proliferating, non-transformed cells could beovercome in cells expressing activated H-ras (FIG. 8A). It was foundthat H-ras activation led to increased replication of even WR(p=0.0094), and that VGF deletion did not inhibit viral replication inH-ras activated cells, whereas the TK deletion did (p=0.016). Thisindicates that the tumor selectivity introduced by the gene deletions invvDD is more than a simple preference for proliferating cells, sinceslowly proliferating or even non-proliferating cells could be targetedif they contained mutations in the EGF-R/Ras/MAP Kinase signalingpathway.

In order to determine whether the double deleted vaccinia (vvDD) mightproduce toxicity by targeting normal proliferating cells (such as gutepithelial, bone marrow or ovarian cells), in vivo viral gene expressionwas studied by non-invasive bioluminescence imaging (FIG. 8B) and viralbiodistribution was examined post mortem (FIG. 12). Bioluminescenceimaging following IV delivery of 1×10⁷ PFU of WR or vvDD expressingluciferase showed that both viruses displayed similar initial infectionand viral gene expression patterns (including spleen, lung, liver andtumor) (FIG. 8B). However, the bioluminescent signal from vvDD wasrapidly cleared from most organs other than the tumor, even inimmunodeficient mice, while WR continued to replicate in the targetorgans and spread to other tissues, including bone marrow, skin andbrain (FIGS. 8B and 8C). Although vvDD did produce some points ofinfection outside of the tumor, these appeared transiently and late,indicating secondary spread without replication (data not shown).Recovery of infectious viral units from tissues of mice treated IV with1×10⁹ PFU of vvDD (a lethal dose for WR) revealed that by day 8 aftertreatment the tumor displayed increasing viral titer, with over1,000-fold more viral copies per mg tissue than any other organ, whileall normal tissues were below the limits of detection or showed fallingviral titers (FIG. 12).

The anti-tumor effects of vvDD were then analyzed in immunocompetentmouse models. vvDD had significantly greater anti-tumor effects than aWyeth TK deleted vaccinia strain (the most common vaccinia strain inclinical trials, usually used as a vaccine) when both were deliveredintravenously (FIG. 13). Further studies showed that 1×10⁹ PFU of vvDDwas capable of significant anti-tumor effects when delivered by eithersystemic or intratumoral injection to both immunodeficient mice carryinghuman tumor xenografts and immunocompetent mice bearing syngeneic tumors(FIG. 13).

In order to increase the anti-tumor potential of vvDD, and to suppressthe outgrowth of microscopic tumor deposits that are not vascularized atthe time of IV dosing, the cytokine GM-CSF was inserted into the site ofthe TK gene (under the control of the synthetic E/L promoter); thisvirus was designated JX-963. Because human GM-CSF is not active inrodents but is active in rabbits (Cody et al., 2005), and in order toassess the activity against much larger primary tumors that reproduciblymetastasize, JX-963 was used in a rabbit model with primary (VX2) livertumors and lung metastases (Kim et al., 2006). As in the mouse models,1×10⁹ PFU of intravenous vvDD had significant anti-tumor effects (FIG.9A). The vvDD virus was also capable of inhibiting the outgrowth ofmicroscopic lung metastases. In order to assess additional efficacy dueto concomitant GM-CSF expression, JX-963 was compared directly to vvDD.JX-963 produced greater efficacy against the primary tumor, andcompletely blocked outgrowth of lung metastases. GM-CSF was detected inthe plasma of JX-963 treated mice by ELISA (data not shown). In additionto direct oncolytic effects, JX-963 was also found to cross-protect theanimal against the tumor by raising a CTL response against the VX2 tumorcells (FIG. 9B).

One concern in using vaccinia virus as an anti-tumor agent is that, eventhough systemic delivery to the tumor is initially possible in naïveindividuals, the immune response raised by prior exposure to the virusmay inhibit the efficacy of subsequent treatment. A strong anti-viralantibody response was raised within 3 weeks of initial infection in therabbits tested (FIG. 14). To study the feasibility of repeat dosingafter neutralizing antibody formation, four rabbits that had initiallyresponded to treatment but had tumor progression after four weeks off oftherapy were re-treated. 1×10⁹ PFU of JX-963 delivered intravenously at6 weeks after the initial treatment resulted in a decrease in primarytumor size in 3 of 4 animals treated (FIG. 9C).

Therefore, by selecting vaccinia virus, that has evolved to spreadthrough the hematopoietic system, and screening strains for tumorselective replication the inventor was able to find a virus capable ofsystemic tumor delivery with rapid oncolytic effects. In order toimprove the safety of this virus several deletions capable of increasingits therapeutic index were introduced, their mechanism of actiondescribed and their biodistribution examined in vivo. Dramatictherapeutic effects against large primary tumors following systemicdelivery were demonstrated. Finally, because it is unlikely all tumorcells will be infected, even following systemic viral delivery, GM-CSFwas expressed from this viral backbone. The addition of GM-CSF was foundto increase the effectiveness of this virus against primary tumors,prevent the outgrowth of micrometastases, and produced an anti-tumor CTLresponse. This indicates that this virus, JX-963, is capable of systemicdelivery to tumors, where it rapidly and efficiently destroys tumortissue, while sparing normal organs, and at the same time induces animmune response within the tumor that is capable of recognizing tumorantigens produced in situ. Repeat dosing was further shown to produceadditional anti-tumor effects, either by direct oncolysis or by boostingthe anti-tumor immune response. JX-963 therefore has the potential toeffectively treat a variety of tumors.

Example 5 Treatment of Hepatic Carcinoma

A. Objectives

(1) To determine the maximally-tolerated dose (MTD) and/ormaximum-feasible dose (MFD) of JX-594 administered by intratumoral (IT)injection, (2) To evaluate the safety of JX-594 administered by I.T.injection, (3) To evaluate the replication/pharmacokinetics of JX-594administered by I.T. injection, (4) To evaluate the immune response toJX-594 and to tumor-associated antigens following I.T. injection(increased inflammatory infiltration at the injected and non-injectedsites; neutralizing antibody formation; cytokine responses; and tumorand virus specific Tlymphocytes induction), (5) To evaluate theanti-tumoral efficacy of JX-594 administered by I.T. injection at theinjected and non-injected sites

B. Study Design

This is a Phase I, open-label, dose-escalation study in hepaticcarcinoma patients with superficial injectable tumor nodule(s) underimaging guide. Patients who have refractory tumors will receive onetreatment of the following four dose levels in a sequential doseescalating design: Cohort 1: 1×10⁸ pfu, Cohort 2: 3×10⁸ pfu, Cohort 3:1×10⁹ pfu, Cohort 4: 3×10⁹ pfu

Target period of such a study will be 15 months. The enrolled patientswill receive 1 treatment per cycle. If a patient receives the treatmentwithout a dose-limiting toxicity (DLT) and the target tumor has notprogressed, the patient will move on to an additional cycle up to atotal of 4 cycles. If a patient has target tumor progressed or iswithdrawn from the study due to a DLT or other reasons, the patient willconduct an End of Study Visit and go into the follow-up phase. A cycleis defined as 3 weeks. A DLT will be observed only at the first cycle.

A dose can be distributed into 1-3 lesions. The sum total of the maximaldiameters of the lesion(s) to be injected must be less than 10 cm. Threepatients will be treated at each dose level unless a DLT is observed.Enrollment will proceed to the next dose level if 0 of 3 patientsexperiences a DLT; if one of the first 3 patients experiences a DLT,then an additional patient will be enrolled until a second DLT occurs(which is defined as the toxic dose at this time) or until a total ofsix patients has been treated. If a second DLT doesn't appear in thecohort, the patient advances to the next dose level.

MTD is defined as the dose immediately preceding the dose at which 2patients experience a DLT after the treatment with JX-594. MFD isdefined as the top dose level when MTD is not defined. When MTD/MFD aredefined, six additional patients will be treated in order to obtain moredata of the safety and toxicity at this dose level. If MTD doesn't occurin Cohort 4 and the efficacy of PR develops in over 2/3 at the previouscohort dose, the clinical study of 6 additional patients will beconducted with this dose.

DLT is defined as any one of the following, attributed to JX-594: 1.Grade 4 toxicity of any period 2. □ Grade 3 toxicity (excluding flu-likesymptoms: fatigue, nausea, myalgia, fever) lasting >5 days. The NationalCancer Institute common Toxicity Criteria of the US will be used toassign the severity of toxicity occurring in this study.

1. Decision on Control Tumor(s) (Non-Injected Tumor(s)) (Cycle 1) andJX-594 Injection (Cycle 2+)

During Cycle 1 the investigator will decide control tumor site(s). Thecontrol tumor(s) must be a clear tumor nodule located in the lobes otherthan hepatic lobes of the target tumor(s) and be outside the lymphaticdrainage of the target tumor(s). Accordingly, control tumor(s) will belocated separately in the left and right lobes of the liver. However, iftumor nodules exist within the limit of one side of the liver, controltumor(s) may be non-injected tumor nodule(s) with JX-594; however acontrol tumor may not be established if the tumor has an extensivesingle nodule. This control tumor will be assessed in identical fashionto JX-594 treated tumor(s). This will enable an assessment of thecontrol effect on tumor growth and local toxicity/activity.

If this patient advances to Cycle 2, the control tumor(s) will beinjected with JX-594 at the same dose level as the targeted tumor inCycle 1. As described above, the dose will be distributed among thetumors proportionally based on the tumor size.

2. Non-Target (Non-Injected) Tumor Responders

Non-injected tumors may respond in this study; this phenomenon has beenreported in a previous Phase I trial of JX-594 with such patients. It isnecessary to understand the mechanism of this effect; possibilitiesinclude spread of the virus from the injected tumors and/or induction oftumor-specific cytotoxic (tumor infiltration of T-lymphocytes (CTL) andsubsequent cytotoxic T-lymphocytes-mediated tumor destruction). In orderto better understand the mechanism(s) of this effect, the investigatorswill perform the following. If a non-injected tumor(s) respondsclinically, core biopsies or fine needle aspirates will be performed atthe same collection time points as the injected tumor (See Appendix A;total non-target tumor biopsies do not to exceed two sites). Specimensfrom non-injected tumors will be analyzed with same method as will beused for materials to be obtained from the injected tumor.

C. Patient Selection

1. Inclusion Criteria

Typically, patients will meet all the following criteria: (1) older than18 years of age, (2) clinically or histologically confirmed (primary ormetastastic) hepatic carcinoma patients with superficial injectabletumor 10 cm longest diameter) under imaging guide, which has progresseddespite of standard therapies (i.e. refractory to standard therapies),(3) progressed tumor despite of standard treatments such as surgicalresection, intraarterial chemoembolization, chemotherapy, and radiationtherapy, (4) Patients with Karnofsky Performance Status (KPS) of ≧70,(5) Patients with anticipated survival of at least 16 weeks, (6) Ifsexually active patients, patients have willingness to use acontraceptive method for 3 months after the treatment with JX-594, (7)Patients with ability to understand and willingness to sign a writteninformed consent, (8) Patients with ability to comply with the studyprocedures and follow-up examinations, (9) Patients with adequate bonemarrow function: WBC>3,000 cells/mm3, ANC>1,500 cells/mm3, hemoglobin>10g/dL, and platelet count>75,000 cells/mm3, (10) Patients with adequaterenal function: serum creatinine <1.5 mg/dL, (11) Patients with adequatehepatic function: serum AST (≦2.5 of ULN), ALT (≦2.5 of ULN), totalbilirubin (≦2.0 mg/dL); for primary lung cancer the patients should beclassified to A or B by Child-Pugh classification.

2. Exclusion Criteria

Patients must not meet any of the following exclusion criteria: (1)Pregnant or nursing an infant, (2) HIV patients, (3) Patients classifiedto C by Child-Pugh classification; patients with total bilirubin>2 mg/dLamong patients classified to A or B (in case of primary hepatic cancer),(4) Patients with clinically significant active infection oruncontrolled medical condition (e.g., respiratory, neurological,cardiovascular, gastrointestinal, genitourinary system) considered highrisk for new experimental drug treatment, (5) Patients with significantimmunodeficiency or family member with the condition due to underlyingillness and/or medication taken, (6) Patients with history of eczemarequiring systemic therapy, (7) Patients with unstable cardiac diseaseincluding MI, unstable angina, congestive heart failure, myocarditis,arrhythmias diagnosed and requiring medication within 6 months prior topatient enrollment of the study, or any other clinically significantcondition in cardiac status, (8) Patients who received systemiccorticosteroid or any other immunosuppressive medication within 4 weeksprior to study drug treatment, (9) Patients who received any otherinvestigational drug study, radiotherapy, chemotherapy or surgery within4 weeks prior to patient enrollment of the study, (10) Patients enableor unwilling to give a written informed consent, (11) Patients withhypersensitivity to ingredient(s) of the study drug.

D. Study Visit Procedures

A summary table of the study procedures is presented in the Schedule ofObservations and Tests. Usually, +1/−1 day window from the scheduled daymay be allowed, and weekends and holidays are not counted.

1. Screening Visit (Day—14 to 0)

This is a clinical study using viruses and the study will proceeded,discussing with the patient. Any patient who wants to take part mustprovide a written informed consent. After signing an informed consent,each patient will conduct the following assessments within 14 daysbefore the initiation of the study:

Clinical Assessments include (1) A thorough medical and surgicalhistory, including anti-cancer treatments, (2) Weight and vital signs(temperature, pulse rate and blood pressure), (3) Physical examination(whole body systems), (4) Karnofsky Performance Score, (5) Chest x-rays(posterior-anterior and bilateral), (6) 12-lead ECG (acceptable if donewithin 3 months prior to patient enrollment of the study), (7)Concomitant medication assessment (all medications taken within 14 daysprior to patient enrollment of the study).

Laboratory Assessments include (1) Routine blood test (includingplatelet count and differential counts), (2) Serum chemistries; sodium,potassium, BUN, creatinine, ALT, AST, alkaline phosphatase, totalbilirubin, LDH, calcium, phosphorus, magnesium, random glucose, totalprotein, albumin and uric acid, (3) Coagulation test: prothrombin time(PT), partial thromboplastin time (PTT), and International NormalizedRatio (INR); fibrinogen, (4) HIV, HBV and alpha Fetoprotein test, (5)Neutralizing antibody titer, (6) Viral genomes (Q-PCR), (7) Routineurinalysis (including microscopic examination), (8) Pregnancy test (forwomen of childbearing potential), (9) Test of appropriate tumor markers(CAl25, CEA, AFP, PSA, CA19-9, etc.) at the screening test, depending onthe type of tumor; when it is increased, the test will be performed onthe 22nd day of each cycle.

Imaging-based Assessments and Measurement of Tumor include measurementof a tumor nodule using abdomen CT scan (Measurement of longestdiameter); may be replaced with CT taken on Day 1 (before thetreatment). (Acceptable if done within 2 weeks prior to patientenrollment of the study).

Day 1 (Cycle 1-4)—It should be noticed which assessments are to beperformed before or after the administration of JX-594.

Day 1; Pre-treatment—Clinical Assessments: Physical examination (wholebody systems), Weight and vital signs (temperature, pulse rate and bloodpressure), Karnofsky Performance Score, Identification of concurrenttherapies, Test and assessment of target tumor(s), Measurement of targettumor(s) (n=1-3); measurement of additional non-injected tumor(s),(n=1-3), Biopsy of target tumor(s).

Laboratory Assessments: Blood—1. Routine blood test (including plateletcount and differential counts), 2. Serum chemistry test: sodium,potassium, BUN, creatinine, ALT, AST, alkaline phosphatase, totalbilirubin, LDH, calcium, phosphorus, magnesium, random glucose, totalprotein, albumin and uric acid, 3. Coagulation test: prothrombin time(PT), partial thromboplastin time (PTT), and International NormalizedRatio (INR); fibrinogen, 4. Cytokines (including GM-CSF), 5.Neutralizing antibody titer, 6. Viral genomes (Q-PCR)

Laboratory Assessments: Others—1. Urine test for pfu, 2. Throat swab forpfu

Study Drug Administration—1. Administration of JX-594 as described inChapter 8

Day 1: Post-treatment—1. Physical examination. Vital signs will be takentwice an hour (30 minutes and 60 minutes) for 6 hours and will be takenroutinely later, 2. Blood will be drawn for the cytokine analysis at thefollowing time-points: 1 hour and 3 hours post-treatment, 3. Blood willbe drawn for the measurement of circulating JX-594 genomes at thefollowing, time-points: 10-15 minutes, 25-35 minutes and 4-6 hours afterthe start of administration, 4. Urine and throat swab samples for viralshedding will be taken 3-4 hours post-treatment, 5. Record of sideeffects and concurrent illnesses

Day 3 (Cycle 1-4)—Laboratory Assessments: Blood—1. Routine blood test(including platelet count and differential counts), 2. Serum chemistrytest: sodium, potassium, BUN, creatinine, ALT, AST, alkalinephosphatase, total bilirubin, LDH, calcium, phosphorus, magnesium,random glucose, total protein, albumin and uric acid, 3. Coagulationtest: prothrombin time (PT), partial thromboplastin time (PTT) andInternational Normalized Ratio (INR); fibrinogen, 4. Cytokines(including GM-CSF), 5. Neutralizing antibody titer, 6. Viral genomes(Q-PCR).

Laboratory Assessments: Others—1. Urine test for pfu, 2. Throat swab forpfu

Clinical Assessments—Record of side effects and concurrent illnesses

Imaging-based assessments: abdomen CT scan when suspicious of sideeffects at clinical Assessments.

Day 5 (Cycle 1-4)—Clinical Assessments—Record of side effects andconcurrent illnesses.

Laboratory Assessments: Blood—1. Routine blood test (including plateletcount and differential counts), 2. Serum chemistry test: sodium,potassium, BUN, creatinine, ALT, AST, alkaline phosphatase, totalbilirubin, LDH, calcium, phosphorus, magnesium, random glucose, totalprotein, albumin and uric acid, 3. Coagulation test: prothrombin time(PT), partial thromboplastin time (PTT), and International NormalizedRatio (INR); fibrinogen, 4. Viral genomes (Q-PCR).

Day 8 (Cycle 1-4)—Clinical Assessments—Physical examination, CT scan;

-   -   biopsy of target tumor(s) (Biopsy will also be performed on up        to 1 or 2 non-injected tumor(s) which shows a significant change        including inflammation, necrosis or shrinkage, etc.). Biopsy        will be performed only at Cycle 1 and 2 by the PI's subjective        evaluation of the patient condition. Record of side effects and        concurrent illnesses.

Laboratory Assessments: Blood—1. Routine blood test (including plateletcount and differential counts), 2. Serum chemistry test: sodium,potassium, BUN, creatinine, ALT, AST, alkaline phosphatase, totalbilirubin, LDH, calcium, phosphorus, magnesium, random glucose, totalprotein, albumin and uric acid, 3. Coagulation test: prothrombin time(PT), partial thromboplastin time (PTT) and International NormalizedRatio (INR); fibrinogen, 4. Cytokines (including GM-CSF), 5.Neutralizing antibody titer, 6. Viral genomes (Q-PCR).

Laboratory Assessments: Others—1. Urine test for pfu, 2. Throat swab forpfu 3. Fine needle aspiration of the necrosis when necrosis occurs(performed only at Cycle 1 and 2).

Day 15 (Cycle 1-4)—Clinical Assessments—Physical examination.

Laboratory Assessments: Blood—1. Routine blood test (including plateletcount and differential counts) 2. Serum chemistry test: sodium,potassium, BUN, creatinine, ALT, AST, alkaline, phosphatase, totalbilirubin, LDH, calcium, phosphorus, magnesium, random glucose, totalprotein, albumin and uric acid, 3. Coagulation test: prothrombin time(PT), partial thromboplastin time (PTT) and International NormalizedRatio (INR); fibrinogen, 4. Viral genomes (Q-PCR).

Laboratory Assessments: Others—1. Urine test for pfu, 2. Throat swab forpfu

Day 22 (Cycle 1-4)—Clinical Assessments—1. Physical examination, 2.Imaging-based assessments: abdomen CT scan (performed at Cycle 2 and 4only), 3. Measurement of target tumor(s) (n=1-3); measurement ofadditional non-injected tumors (n=1-3), 4. Biopsy of target tumor(s)(Biopsy will also be performed on up to 1 or 2 non-injected tumor(s)which show a significant change including inflammation, necrosis orshrinkage.), 5. Record of side effects and concurrent illnesses, 6. Day22 may be used as Day 1 pre of the following cycle. There may be up toone week interval between Day 22 and Day 1 of the following cycle.

Laboratory Assessments: Blood—1. Routine blood test (including plateletcount and differential counts), 2. Serum chemistry test: sodium,potassium, BUN, creatinine, ALT, AST, alkaline phosphatase, totalbilirubin, LDH, calcium, phosphorus, magnesium, random glucose, totalprotein, albumin and uric acid, 3. Coagulation test: prothrombin time(PT), partial thromboplastin time (PTT) and International NormalizedRatio (INR); fibrinogen, 4. Neutralizing antibody, 5. Viral genomes(Q-PCR), 6. Test of appropriate tumor markers (CA125, CEA, AFP, PSA,CA19-9, etc.) at the screening test, depending on the type of tumor;when it is increased, the test will be performed on the 22^(nd) day ofeach cycle.

Laboratory Assessments: Others—1. Urine test for pfu, 2. Throat swab forpfu

Day 28 or End of Study Visit—Clinical Assessments—Physical examination,and Record of side effects and concurrent illnesses.

Laboratory Assessments: Blood—1. Routine blood test (including plateletcount and differential counts), 2. Serum chemistry test: sodium,potassium, BUN, creatinine, ALT, AST, alkaline phosphatase, totalbilirubin, LDH, calcium, phosphorus, magnesium, random glucose, totalprotein, albumin and uric acid, 3. Coagulation test: prothrombin time(PT), partial thromboplastin time (PTT) and International NormalizedRatio (INR); fibrinogen, 4. Viral genomes (Q-PCR).

Cycle 3-4—1. A patient whose injection site tumor has not shown >25%increase in longest diameter on Day 22 of Cycle 2 will advance to Cycle3-4, 2. A patient whose injection site tumor has shown 25-50% increasein longest diameter on Day 22 of Cycle 2 may advance to Cycle 3-4, 3. Apatient whose injection site tumor has shown >50% increase in longestdiameter on Day 22 of Cycle 2 will be terminated from the study.

Follow-up and Review of Patients—Patients who have completed theclinical study will be followed up in the fashion of routine follow-upfor hepatic cancer patients for one year after the End of Study visit.Regardless of the clinical study, patients alive may take routine testssuch as hepatoma serum test and imaging-based assessments when theyreturn for a visit to the hospital and take examinations every 3 months.After the completion of the clinical study, if a remarkable clinicalbenefit is determined, up to total 4 times of additional injection maybe administered after obtaining a separate written informed consent. Atthis time, all procedures of the study will proceed in the same fashionas the first 4 administrations of this study. After the completion ofthe study up to Cycle 4, until PI judges there is a significant clinicalbenefit (more than stable disease), up to total 4 times of additionalinjection of the study drug may be administered. In this case, PI shoulddiscuss with the Sponsor in advance and obtain an agreement from theSponsor. All study plans will proceed in the same fashion as thisclinical study.

E. Viral Replication, Spread and Special Tests

1. Q-PCR and Plaque-Forming Unit Assays of Plasma and Urine(Pharmacokinetic Test)

Viral spread to the bloodstream will be assessed by quantitativepolymerase chain reaction (Q-PCR) test. To detect whether viruses arepresent in the urine and throat swabs, samples will be collectedpost-treatment.

2. Tumor Biopsies and Fine Needle Aspirations (Immunity Response Test)

To find out viral replication at the tumor site(s), core biopsies andfine needle aspirations will be conducted (if deemed safe and easy)before and after the treatment. These biopsies will be analyzed forevidence of viral replication, inflammatory and immune cellinfiltration, necrosis and apoptosis.

To obtain tissues, core biopsy needle will be used or fine needleaspiration biopsy will be performed under imaging guide. However,sometimes these biopsies may cause an urgency or dangerous situation tothe patient. Therefore, when doing a biopsy to obtain tissues, thesafety for patient should be the first concern. If a patient's conditionis highly likely to get into a danger (hepatic capsular tumor etc.),tissues should be obtained via a safe route.

If the PI judges that tissue biopsy (fine needle aspiration) is likelyto cause a danger to the patient, biopsy (fine needle aspiration) maynot be carried out. In addition, if needed for the safety of a patient,at the PI's discretion, patients may be hospitalized and observed for upto 5 day before and after administrating a tissue biopsy (fine needleaspiration) and/or intratumoral injection with JX-594.

3. Cytokine Analysis (Immunity Response Test)

Serum concentrations of GM-CSF, IL-1, IL-4, IL-6, IL-10, IFN-δ and TNF-αwill be measured with ELISA assay.

4. Neutralizing Antibody Assay (Pharmacokinetic Test)

The occurrence of neutralizing antibody titer of JX-594 in the seriallydiluted serum of a patient will be identified with a plaque assay.

5. Pharmacokinetic Blood Draws

Pharmacokinetic draw of 3 mL blood each will be taken in a mini yellowtop vacutainer.

F. Administration of Investigational Drugs

1. Dose, Administration and Treatment Schedule

Dose. Doses will typically be as follows: Cohort 1: 1×10⁸ pfu, Cohort 2:3×10⁸ pfu, Cohort 3: 1×10⁹ pfu, Cohort 4: 3×10⁹ pfu.

Drug Administration.

JX-594 can be administered via intratumoral injection. Intratumoralinjections will be administered by an expert physician in the manner asdescribed. Using a 21-gauge needle or smaller, tumors will be injecteddirectly with virus-containing solution whose volume is equivalent toapproximately 25% of the total volume of tumors (1-3 tumors) to beinjected. Typically, injection will be conducted under imaging guide(e.g., under CT). One to three tumors can be injected. Each tumor shouldreceive equal amount of solution. If 2-3 tumors are injected, the volumeof virus solution injected into a tumor will be proportional to thevolume of the tumor over the others (i.e., if a tumor is twice thevolume of the other, the larger tumor will receive 2/3 of the totalvolume of virus solution).

Although the target tumor(s) selected at Cycle 1 may stop growing,injections should be continued at all cycles. However, if necessary, atCycle 3 the investigators may additionally select non-target tumorswhich have not been injected at Cycle 1 and 2, up to three, includingthe target tumor(s) at Cycle 1. The sum of the maximal diameters of theinjected tumors must be 5-10 cm. The dose of intratumorally injectedvirus solution will be proportional to the volume of the tumor.

JX-594 Preparation.

JX-594 is supplied in a frozen (−60° C. or below), single-use glass vialcontaining 150 μl virus formulation (to deliver 0.1 mL). The volume of100 μl contains 1.9×10⁸ pfu virus. The vial should be thawed verticallyat room temperature. JX-594 should not be placed in a hot water bath.Re-suspend with a pipette. While being diluted and carried to a patient,the virus may be stored at 4° C. Thawed JX-594 should not be injectedafter 4 hours.

A senior pharmacist and other designated pharmacists should store JX-594vertically in biological safety cabinets (Class 2) with caution (use ofgloves, safety glasses, a gown etc.). Initial procedure for alldilutions: When use a syringe, withdraw required volume of sterilesaline solution and transfer to a standardized falcon tube. The finalvolume of the virus plus diluent for injection should be equivalent toapproximately 25% of the target tumor volume.

Cohort 1: One (1) vial of JX-594 will be used to the patients inCohort 1. The prescribed volume of JX-594 transferred to sterile salinesolution will be drawn up with a micropipette/syringe.

Cohort 2: Two (2) vials of JX-594 will be used to the patients in Cohort2. After mixing, the content in the first vial will be transferred tothe second viral. The prescribed volume of JX-594 transferred to sterilesaline solution will be drawn up with a micropipette/syringe.

Cohort 3 and 4: Four (4) or eleven (11) vials of JX-594 will be used foradministration to the patients in Cohort 3 or 4, respectively. Allcontents will be transferred to a mixed small polypropylene tube. Theprescribed volume of JX-594 transferred to sterile saline solution willbe drawn up with a micro-pipette/syringe.

Final procedure for all dilutions: Wrap the tube with aluminum foil orplace it in light-proof bag at room temperature. Vortex vigorously for10 seconds prior to the administration. It should not be injected after30 minutes exposed at room temperature or after 4 hours thawed.

Treatment Schedule.

Typically, enrolled patients receive 1 treatment or dose of JX-594 percycle. A patient whose JX-594-injected target tumor has not progressedat the end of a cycle will receive the treatment at the subsequent cycle(up to a total of 4 cycles). A patient whose target tumor has progressedwill terminate visits. A cycle is defined as 3 weeks. A dose can bedivided evenly among 1-3 lesions. The sum of the maximal diameters ofthe injected lesions must be ≦10 cm.

Dose Escalation.

In the dose escalation phase of the clinical study, 2-6 patients will beenrolled per each cohort. If none of the first 3 patients experience aDLT, the study will proceed to the next cohort. If a DLT occurs in oneof the first 3 patients in a cohort, the study will proceed until up toa total of 6 patients will be enrolled to the cohort or 2 patientsincluding the first one experience a DLT.

If less than 2 patients out of 6 in Cohort 1 experience a DLT up to 2weeks following the first injection, the study will advance to the nextcohort. If 2 patients experience a DLT, the immediately preceding dosewill be defined as the MTD.

Second patient will not enroll until 1 week after administrating thefirst injection to the first patient at Cycle 1; this rule applies tothe next patient's entry. If a DLT occurs in a cohort, all subsequentlyenrolled patients will start treatment at 2 weeks after completing thefirst injection at Cycle 1 to all previously enrolled patients. Patientswill enter for the cohort of the next dose level at least 2 weeks afterthe last patient in the previous cohort completes the first injection atCycle 1.

If more than 2 patients in Cohort 1 experience a DLT, the clinical studywill be discontinued.

G. Safety

After treatment, systemic side effects may occur: Fever, chills,myalgia, fatigue/asthenia, nausea, and vomiting. Side effects at theinjected tumor site such as pain, necrosis, ulceration and inflammationmay occur. In the light of experience on pre-clinical study and GM-CSFclinical study, temporary increase in lymphocyte, monocyte, or whiteblood cell accompanied with increased neutrophilia may occur. Thefollowing may occur at the injected tumor site: Pain, necrosis,ulceration and inflammation.

Although highly unlikely and not described on the previous Phase I trialwith JX-594, a disseminated vaccinia-associated rash or encephalitis istheoretically possible; these complications have been described inapproximately 1 in 10,000 and 1 in 1,000,000 vaccine recipients,respectively.

1. Dose-Limiting Toxicity (DLT)

DLT is defined as any Grade 3 or more toxicity attributed to JX-594,excluding flu-like symptom(s) (e.g., fatigue, nausea or myalgia),lasting longer than 5 days or any Grade 4 toxicity of any durationattributed to JX-594.

Security of Safety for Patients from Risk of Procedure. Biopsy may causecomplications such as intra-peritoneal bleeding and/or shock due tobursting of the tumor. Although the incidence of reported complicationis <0.1% and can be cured with transcatheter embolization, the safetyfor patient should be the first concern. Therefore, if the treatingphysician judges that a biopsy is likely to cause a danger to thepatient, the biopsy may not be carried out. In addition, if needed forthe safety of a patient, at the PI's discretion, patients may behospitalized and observed for up to 5 day before and after undergoing abiopsy and/or intratumoral injectino with JX-594.

H. Efficacy

The primary objective of such a study is a Phase I clinical study forsafety, not a clinical benefit. Nevertheless, this study is expected tocause shrinkage of the injected and/or non-injected tumor(s) due todirect viral effect (i.e., oncolysis effect) and/or immune-mediatedtumor destruction induced by the treatment.

The criterion of efficacy assessment is changes in target lesions. Ifany changes in non-target lesions, they will be evaluated based on theresponse of target lesions with reference to the table below.

Evaluation of Target Lesions.

Complete Response (CR): Disappearance of all target lesions PartialResponse (PR): At least a 30% decrease in the sum of LD of targetlesions taking as reference the baseline sum LD. Progressive Disease(PD): At least a 20% increase in the sum of LD of target lesions takingas references the smallest sum LD recorded since the treatment started.Stable Disease (SD): Neither sufficient shrinkage to qualify for PR norsufficient increase to qualify for PD taking as references the smallestsum LD since the treatment started.

The evaluation criteria of overall response are presented in thefollowing table. The best overall response means the best responserecorded from the starting point of the treatment until diseaseprogression/recurrence.

TABLE 3 Evaluation of best overall response Target lesions Non-targetlesions New lesions Overall response CR CR No CR CR Non-CR/Non-PD No PRPR Non-PD No PR SD Non-PD No SD PD Any Yes or No PD Any PD Yes or No PDAny Any Yes PD CR = Complete Response; PR = Partial Response; SD =Stable Disease; PD = Progression

Note: Patients with a global deterioration of health status requiringdiscontinuation of treatment without objective evidence of diseaseprogression at that time should be classified as having “symptomaticdeterioration.” Every effort should be made to detect the objectivedisease progression, even after discontinuation of treatment.

In some circumstances, it may be difficult to distinguish residualdisease from normal tissue. When the evaluation of complete responsedepends on this determination, it is recommended that the residuallesion be investigated (fine-needle aspiration/biopsy) before confirmingthe complete response status.)

Guideline for Evaluation of Measurable Lesions.

All measurements should be taken on the last day of Cycle 2 (Day 22) andthe last day of Cycle 4 (Day 22) by CT or MRI and recorded in metricnotation by use of a ruler or calipers. All baseline evaluations shouldbe performed as closely as possible to the beginning of treatment andnever more than 4 weeks before the beginning of the treatment.

Note: Lesions that have been previously irradiated is not acceptable asmeasurable lesions. If these lesions are considered acceptable asmeasurable lesions at the investigator's discretion, condition forconsideration of these lesions should be described in the protocol. Alsonote that tumor lesions that are situated in a previously irradiatedarea might not be considered measurable. If the investigator considersit is appropriate as measurable lesions, the conditions under which suchlesions should be considered must be defined in the protocol.

The same method of assessment and the same technique should be used tocharacterize each identified and reported lesion at baseline and duringfollow-up. Imaging based evaluation is preferred to evaluation byclinical examination when both methods have been used to assess theanti-tumor effect of a treatment.

Conventional CT should be performed with contiguous cuts of 10 mm orless in slice thickness. Spiral CT should be performed using a 5 mmcontiguous reconstruction algorithm. If applicable, PET-CT may beperformed in the screening visit and in this case PET-CT should be usedin the assessment on Day 22 of Cycle 2. If necessary, PET-CT may berepeated on Day 22 of Cycle 4.

Confirmation of Measurement/Duration of Response.

Confirmation: To be assigned a status of PR or CR, changes in tumormeasurements must be confirmed by repeat assessments that should beperformed at 8 weeks after the criteria for response are first met. Inthe case of SD, follow-up measurements of minimum 16-week interval musthave met SD criteria at least once after study entry.

Duration of Response:

The duration of overall response is defined as the time from date offirst documented CR or PR (whichever documented first) to the earliestof date of objectively confirmed recurrence or progressive disease(taking as reference for progressive disease the smallest measurementsrecorded since the treatment started). The duration of overall completeresponse is defined as the time from date of first documented CR to theearliest of date of objectively confirmed recurrence.

Duration of Stable Disease:

SD is defined as the time from date of first documented SD after thetreatment to the earliest of date of objectively confirmed PD (takingthe smallest measurements recorded since the treatment started asreference).

Reassessment of Tumor Response.

If needed, independent radiologists of this study will assess tumorresponse. However, the assessments result will be used for the studypurpose only and will not affect clinical conclusion.

I. Statistical Methods and Data Analysis

1. Sample Size

The estimated sample size will be 18 patients and the possible rangewill be 2-30 patients. The primary objectives of the study are todetermine the safety and MTD or MFD of JX-594 by intratumoral injection.This study represents the 2nd clinical trial of JX-594 in humans.Because there are not previous clinical studies in human which are basedon meaningful statistical calculations, the sample size for this studyis selected based upon clinical safety considerations. The results ofthe study may be used to provide estimates of variability fordetermining sample size requirements for future clinical studies.

The patients in each cohort have a chance to stop the study beforereaching the actual MTD as well as a chance to advance beyond the actualMTD. The tables below show the statistical likelihood of each outcomebased on the true DLT incidence. The table below presents theprobabilities (various true incidences given to each patient population)of each outcome in a cohort of the first 3 patients.

TABLE 4 # DLTs True Incidence of DLT in in a Patient Population Cohortof 0.1 0.2 0.3 0.4 0.5 3 Patients Action Probability of each outcome 0Advance to next cohort 0.729 0.512 0.343 0.216 0.125 1 Enroll additional3 patients 0.243 0.384 0.441 0.432 0.375 ≧2 Stop treatment, define 0.0280.104 0.216 0.352 0.500 MTD

The following table shows the probabilities of each outcome in a cohortof 6 patients. After observing 1 DLT in the first 3 patients in thecohort and adding 3 more patients to the cohort, it represents varioustrue incidences in the given patient population.

TABLE 5 # DLTs True Incidence of DLT in in a Patient Population Cohortof 0.1 0.2 0.3 0.4 0.5 6 Patients Action Probability of each outcome 0NA NA NA NA NA NA 1 Enroll additional 3 patients 0.177 0.197 0.151 0.0930.047 ≧2 * Stop treatment, define 0.066 0.187 0.290 0.339 0.328 MTD * 1patient out of the 1st 3 and 1 patient out of the 2nd 3

2. Statistical Methods/Data Analysis

The population to be summarized will be an intent-to-treat (ITT)population, defined as all patients to have received at least onetreatment with JX-594. In addition, an evaluable patient population willalso be assessed as a subset of the ITT population. Evaluable patientsare those to have received at least one cycle of therapy withappropriate tumor measurement being performed at a proper time period ofthe pre- and the post-treatment.

This study will proceed with four treatment cohorts to have two to sixpatients according to the cohort. The data for each cohort will besummarized with appropriate descriptive statistics, frequencytabulations, graphs, and data listings. The data from the treatmentcohorts will be combined for selected data displays. Specific datadisplays to be generated are described below.

Subject age, weight, and height will be summarized with descriptivestatistics (mean, median, standard deviation, minimum and maximum),while gender and race will be summarized with frequency tabulations. Thedata for the treatment cohorts will be summarized separately for eachpatient as well as combined. To do this, individual patient listingswill be produced. Physical medical history data will be separated foreach treatment cohort and will be combined to summarize with frequencytabulations. Treatment administration will be summarized withdescriptive statistics (mean, median, standard deviation, minimum andmaximum). Any patients who receive the study drug will be included inthe safety analysis. Safety data including adverse events, laboratoryresults, toxicity, vital signs and withdrawal information will beseparately summarized at the time of termination of each treatmentcohort. AEs will be coded and tabulated using the COSTART body systemclassification scheme. The number and percent of subjects who have AEswill be tabulated by treatment cohort and treatment purpose; inaddition, the data will be stratified by the severity of AE andinvestigator-specified relationship to JX-594.

Laboratory results will be summarized, at the time of termination, withshift tables displaying the numbers of patients with changes from pre-to post-treatment. Laboratory results of selected variables will bedisplayed graphically.

In addition to the overall tumor response rates, tumor response rates atthe target and nontarget sites will be reported. Time-to-tumorprogression at the target and non-target sites will be reported andoverall survival will also be reported. As this is an uncontrolled,nonrandomized study with a small number of patients in each group,hypothesis to test data from this study alone is not assumed. In orderto assess differences between treatment cohorts, either parametric ornonparametric methods may be used to compare each group, as appropriate.

Example 6 Treatment of Unresectable Malignant Melanoma

A. Dose and Schedule

1. Rationale for Dose and Schedule

A total dose per treatment of 1×10⁸ pfu will be given. This dose islower than the top weekly dose of 1.6×10⁸ pfu, which was safelyadministered in the first Phase I study of JX-594 for the treatment ofsurgically incurable cutaneous melanoma (Mastrangelo et al., 1998).Furthermore, 1×10⁸ pfu is ten times lower than the top dose that hasbeen safely administered to date (n=2 patients) in the ongoing Phase Iintratumoral (IT) trial with JX-594 and three times lower than the topdose level cleared to date. In that trial, treatments by IT injectioninto 1-3 liver tumors are administered every three weeks. Preliminaryresults from this study reveal that flu-like symptoms and hematologyparameters recover to baseline levels typically within 4 days (i.e., Day5) after treatment with JX-594.

A weekly dosing regimen was chosen because patients in all cohortsrecovered from mild to moderate treatment-related toxicities by Day 5 inthe ongoing liver IT study described above. Furthermore, data fromMastrangelo et al. 1998 indicate that twice weekly IT injections of upto 8×10⁷ pfu per treatment are safe and effective.

As evidenced by the initial Phase I/II melanoma study (Mastrangelo etal., 1998), patients were found to have developed a significant humoralimmune response to vaccinia virus within 14-21 days followingre-vaccination. Antibody titers were found to reach a plateau at 4-6weeks following exposure despite continuing treatments. Therefore, thisprotocol investigates weekly IT administration for six weeks in order toconfer maximum possible delivery and JX-594 anti-tumoral effects priorto the development of high titer antibodies and T cells.

2. Rationale for Study

Melanoma may be the optimal target for JX-594 immunotherapy because ofthe relatively high rate of accessible disease for injection, thepositive response of melanoma seen with IL-2 immunotherapy, and the lackof effective, tolerable therapy for patient with metastatic melanoma.Furthermore, it is contemplated that JX-594 replication targets the EGFRpathway, which is highly expressed in melanocytes.

Results from an initial Phase I/II study suggest that intratumoralinjection of JX-594 is safe and effective in treating both injected anddistant disease in patients with surgically incurable metastaticmelanoma. Response of both injected tumors (in 5 of 7 patients) andresponse of at least one non-injected tumor (in 4 of 7 patients) wasdemonstrated, including two patients who achieved a partial response (6+months) and a complete response (4+ months) to JX-594 treatment.Particularly noteworthy is that efficacy and gene expression occurreddespite pre-treatment vaccination (and, therefore, pre-existinganti-vaccinia immunity) in all patients.

This study design was selected in order to expand on the initial PhaseI/II study described above and evaluate injected tumor response in up to15 evaluable patients with Stage 3 or Stage 4 unresectable metastaticmelanoma. In addition, JX-594 safety, pharmacokinetics,pharmacodynamics, immune response to JX-594, and expression of theGM-CSF transgene in the blood and tumor tissues will be evaluated. Theinvestigators will also evaluate whether JX-594 is able to spreadintravenously and infect non-injected regional and distant disease,suggesting that it may be able to confer similar anti-tumor effects asthose experienced at the site of direct intratumoral injection. Thisfinding, in addition to adding to the overall clinical experience ofJX-594 administered IT, would strongly support treatment of JX-594 by IVadministration for treatment of advanced/metastatic disease,particularly in the treatment of advanced malignant melanoma.

B. Investigational Product Description

JX-594 is a cancer-targeted, replication-selective vaccinia virusderived from the commonly used Wyeth vaccine strain (Dryvax®, Wyethlaboratories). The virus is derived from a vaccine strain with thymidinekinase (TK) gene inactivated. JX-594 contains the gene and promoter forhGM-CSF, a potent cytokine involved in immune response. JX-594 isfurther modified with the insertion of lacZ gene to allow tracking ofthe virus in tissues.

C. Objectives

Objective include evaluation of (a) the objective response rate ofinjected tumor(s), (b) the safety and toxicity of JX-594 administered byIT injection, (c) the objective response rate of entire disease burdenafter JX-594 administration by IT injection (RECIST criteria), (d) theprogression-free survival (PFS) time, and (e) the response rate ofnon-injected tumor(s).

D. Study Design

1. Study Overview

This is a Phase I/II, open-label trial in patients with unresectableStage 3 or Stage 4 malignant melanoma. Patients will receive a total ofsix (6) intratumoral injections with JX-594 over a period of 6 weeks. Atotal dose of 1×10⁸ plaque-forming units (pfu) will be administered ateach treatment and will be divided evenly among up to five (5) tumors.If patients experience a partial injected tumor response to IT treatmentwith JX-594 after completing 6 treatments, an additional 3 treatmentsadministered weekly may be given.

2. Study Endpoints

Primary endpoints for clinical studies are typically response rate forinjected tumor(s), including complete response rate, partial responserate, and duration of response. Secondary endpoints for such studies caninclude safety, as determined by incidence of treatment-related adverseevents, serious adverse events (SAEs), and clinically-significantchanges from baseline in routine laboratory parameters includingcomplete response rate, partial response rate, duration of response,Progression-free survival (PFS), Response rate of non-injected tumor(s),including complete response rate, partial response rate, and duration ofresponse. Other endpoints may include overall survival, clinical benefit(including weight gain and improvement in performance status), JX-594assessment (e.g., viral genome (Q-PCR) in plasma and/or whole blood;Viral infectious virus in plasma and/or whole blood, optional (plaqueassay)), Immunologic assessment (JX-594 neutralizing antibodies inserum; plasma GM-CSF measurements (ELISA assay)), histologic assessment(viral gene expression in the tissue; GM-CSF expression; lac-Zexpression; inflammatory cell infiltration; necrosis; apoptosis; virusreplication factories within the cytoplasm; EGFR pathway status; andtumor thymidine kinase status).

3. Dose

Typically, virus will be diluted in sterile normal saline as describedin herein. A total dose of 1×10⁸ plaque-forming units (pfu) will beadministered at each treatment and will be divided evenly among up tofive (5) tumors.

4. Overall Study Duration and Follow Up

A study period will typically consist of patient visits for screening,study treatment, and post-treatment follow-up evaluations.

Screening.

Patient eligibility for a study will be determined within 14 days priorto first treatment with JX-594.

Treatment.

Eligible patients will be treated with a dose of 1×10⁸ pfu administeredby intratumoral injection weekly (Days 1, 8, 15, 22, 29, and 36) for atotal of 6 treatments given over 6 weeks. Patients must continue to meetall eligibility criteria before re-treatment. If a treatment is missedfor any reason, the missed treatment will be given the following weekprovided the eligibility criteria are met, and the visit schedule willbe adjusted and patients will be followed accordingly such that thepatient receives a total of 6 treatments. Injections may be delayed fora cumulative maximum of 4 weeks. Patients who have delayed treatmentwill still complete all 6 treatments and will be evaluated for responseone week after their 6th treatment. Assessment of response will beinitially conducted one week after the final dose is administered (i.e.,Day 43). If patients experience a partial injected tumor response to ITtreatment with JX-594 after completing 6 treatments, an additional 3treatments administered weekly may be given.

Post-Treatment Follow-Up.

All patients will return for a follow-up visit 28 days after lasttreatment with JX-594 (i.e., Day 64). For 6 months after completion oftherapy or until patient has progressive disease at the injection site,begins a new cancer therapy, or dies. The patient will return to theclinic every three weeks after the last injection for tumor measurementby physical exam (PE) (if possible) and evaluation of response. Every 6weeks, patient will also have a response assessment by PE and/or CT/MRI.After 6 months of follow-up, patient will return to the clinic every 3months for tumor measurement and response assessments (including CT/MRI)until progressive disease at the injection site, death, or untilinitiation of new cancer therapy.

Long-Term Follow-Up of Gene Therapy Products.

After disease progression at the injection site or initiation of newcancer therapy, patient may continue to be monitored for survival andfor potential long-term effects of gene therapy according to current FDAguidelines. If patients are no longer returning to the clinic fortreatment or post-treatment follow-up, this data may be collected bymail or phone.

E. Study Population

1. Inclusion Criteria

Patients will typically meet all of the following criteria:histologically-confirmed, stage 3 or Stage 4 malignant melanoma; atleast one tumor mass measurable by CT/MRI and/or physical examinationthat can be injected by direct visualization or by ultrasound-guidance;anticipated survival of at least 16 weeks; cancer is not surgicallyresectable for cure; KPS score of ≧70; age ≧18 years; men and women ofreproductive potential must be willing to follow accepted birth controlmethods during treatment and for 3 months after the last treatment withJX-594; understand and willfully sign an Institutional Review Board(IRB)/Independent Ethics Committee (IEC)-approved written informedconsent form; able to comply with study procedures and follow-upexaminations; adequate liver function (total bilirubin ≦2.0×ULN; AST,ALT≦2.0×ULN); adequate bone marrow function (WBC>3,500 cells/mm³ and<50,000 cells/mm³; ANC>1,500 cells/mm³, hemoglobin>10 g/dL; plateletcount>125,000 plts/mm³); acceptable coagulation status (INR<(ULN+10%));and acceptable kidney function (serum creatinine <2.0 mg/dL).

2. Exclusion Criteria

Typically, patients should not meet any of the following exclusioncriteria: target tumor(s) adherent to and/or invading a major vascularstructure (e.g., carotid artery); pregnant or nursing an infant; knowninfection with HIV; systemic corticosteroid or other immunosuppressivemedication use within 4 weeks of first treatment with JX-594; clinicallysignificant active infection or uncontrolled medical condition (e.g.,pulmonary, neurological, cardiovascular, gastrointestinal,genitourinary) considered high risk for investigational new drugtreatment; significant immunodeficiency due to underlying illness and/ormedication (e.g., systemic corticosteroids); history of eczema that atsome stage has required systemic therapy; clinically significant and/orrapidly accumulating ascites, peri-cardial and/or pleural effusions(e.g., requiring drainage for symptom control); severe or unstablecardiac disease which includes, but is not limited to, any of thefollowing within 6 months prior to screening: myocardial infarct,unstable angina, congestive heart failure, myocarditis, arrhythmiasdiagnosed and requiring medication, or any clinically-significant changein cardiac status; treatment of the target tumor(s) with radiotherapy,chemotherapy, surgery, or an investigational drug within 4 weeks ofscreening (6 weeks in case of mitomycin C or nitrosoureas); experienceda severe reaction or side-effect as a result of a previous smallpoxvaccination; inability or unwillingness to give informed consent orcomply with the procedures required in this protocol; patients withhousehold contacts who are pregnant or nursing an infant, children<5years old, have history of eczema that at some stage has requiredsystemic therapy, or have a significant immunodeficiency due tounderlying illness (e.g., HIV) and/or medication (e.g., systemiccorticosteroids) will be excluded unless alternate living arrangementscan be made during the patient's active dosing period and for threeweeks following the last dose of study medication.

3. Other Eligibility Criteria Considerations

Deviations to Eligibility Criteria.

Patients with minor deviations from the above inclusion/exclusioncriteria (e.g., laboratory values outside the pre-specified range) maybe allowed into the study if these deviations are not expected to affectthe patient's safety, the conduct of the study, or the interpretation ofthe study results. Written approval by the study sponsor or sponsor'srepresentative for enrollment of patients with minor deviations shouldbe requested.

4. Patient Enrollment Procedures

Once the investigator conducts the screening evaluations and confirms apatient's eligibility, the sponsor typically reviews screening andeligibility information and provides written verification to theinvestigator for each patient's enrollment. Upon confirming enrollment,the patient will be assigned an identifier using a pre-defined patientnumbering scheme. The patient identifier will be a composite of studynumber, site number, patient number and patient initials.

F. Investigational Product

JX-594 will be supplied by Jennerex Biotherapeutics. Typically, JX-594is formulated as a liquid and is stored frozen in glass vials designedfor single use. Each vial contains 0.15 mL. The virus solution is acolorless to slightly yellow solution that is clear to slightlyopalescent. The concentration of JX-594 is 1.9×10⁹ pfu/mL.

JX-594 is considered a Biosafety Level 2 (BSL-2) infectious substance.The BSL-2 designation and associated guidelines apply to agents ofmoderate potential hazard to personnel and the environment. Examples ofother BSL-2 agents include the measles virus, salmonellae and theHepatitis B virus. Institutional infection control policies should beconsulted.

JX-594 is typically stored in a monitored, secure freezer withrestricted access. JX-594 will be stored in clearly-labeled vials withinsecondary packaging at −60° C. or below with appropriate bio-hazardlabeling (indicating the nature of the agent) on the freezer door andthe door of the room. Freezers should have an alert limit set at −65° C.to allow time to respond before freezer temperature rises to −60° C. Anextended time at >−60° C. will require placing affected material onquarantine until the titer can be reconfirmed.

Worksheets designed to ensure proper handling and preparation of JX-594will be provided to a study site with supplemental study information.Institutional infection control policies for preparation, transport, anddisposal of viral vectors [Biosafety Level 2 (BSL-2)] should beconsulted and followed. Gloves, gown and ocular shield should be worn atall times. All work with JX-594 will be carried out in a verticalbiological safety cabinet (class 2) in accordance with BSL-2 handlingguidelines in a pharmacy/laboratory under the direction of an accreditedpharmacist/scientist. The hood itself will be wiped down with 70%ethanol before and after each use.

Thawing.

Thawing should occur at room temperature with the vial upright. JX-594should not be placed in a hot water bath. Once thawed, place the vial in15 mL polypropylene conical centrifuge tube (e.g., Corning or Falcon),cap the tube, and centrifuge at 100×g for 2 minutes. Remove the vial ofJX-594 from the polypropylene tube with forceps or equivalent. Virusformulation must be stored on ice or refrigerated (2-8° C.) untildiluted and delivered to patient. Infusion should not begin more than 4hours after virus formulation has been thawed.

Preparation.

After centrifugation of a vial, gently re-suspend with micropipettor(200 μL micropipettor set to 100 μL suggested). Care must be taken notto blow bubbles into the formulation. Approximately 2.75 mL of virussolution (JX-594+ saline) is typically prepared, which will bedistributed into 5 syringes of 0.5 mL/each. Using a micropipettor,transfer 2.64 mL of sterile normal saline to an appropriately-sizedpolypropylene tube (e.g., 5 mL Falcon tube). From one (1) vial ofJX-594, draw up 116 μL of JX-594 and transfer to the Falcon tubecontaining the saline. Replace the cap on the Falcon tube, shield thetube from light (with foil or place in light-proof receptacle), andimmediately place the covered tube at 2-8° C. (refrigerate or place onwet ice).

Within 30 minutes prior to administration, vortex vigorously for 10seconds. After vortexing, draw up 0.5 mL of the virus solution (JX-594+saline) into each of 5 syringes. Cap the syringes and deliver to theinvestigator for injection. Do not begin injection more than 4 hoursafter virus formulation has been thawed. Virus formulation must bestored on ice or refrigerated (2-8° C.) until diluted and delivered topatient.

1. Administration of JX-594

JX-594 will be administered by intratumoral injection every week for atotal of six (6) injections over six weeks. Administration will be doneon Days 1, 8, 15, 22, 29, and 36. Patients will receive a dose of 1×10₈pfu per treatment divided over ≦5 lesions. Only lesions accessible fortreatment via percutaneous injection (e.g., palpable skin nodules orlymph node metastases) or ultrasound (US)-guided injection will beeligible for treatment.

The Investigator will determine at each treatment which lesions (tumors)to inject. Tumors will be injected based on size; the largest lesionsshould be injected at each treatment. At the investigator's discretion,one or more syringes may be used to treat a tumor.

After aseptic skin preparation at the needle entry site(s), a localanesthetic will be administered. An 18-22 gauge needle will be used forinjection. The injection needle will be introduced into the tumor asdescribed below. Injections will be done by the principal investigatoror sub-investigator.

Injection into each tumor will be done by injecting the entire syringevolume (0.5 mL) into 4 equally-spaced needle tracts per tumor radiatingout from the central puncture site. As an example, the virus injectioncan be performed as follows: (1) insert the needle (18-22 gauge) intothe center of the tumor, (2) extend the needle toward the edge of thetumor (to within 1-3 mm of the edge of the tumor), (3) inject about 25%of the syringe volume (approximately 0.125 mL) while pulling backtowards the central puncture site, (4) without withdrawing the needlecompletely from the tumor, repeat the steps above at spacing of 90° fora total of 4 needle tracks.

Expected Toxicities.

The following systemic toxicities are expected following treatment:fever, chills, anorexia, myalgia, fatigue/asthenia and/or headache.Transient decreases are expected in neutrophils, lymphocytes, plateletsand hematocrit. Hematologic parameters typically returned to baselinelevels by Day 5 (typical duration 2-3 days). For Cycle 1 only, anincrease of leukocytes within the first four days following the initialinjection is possible. Total white blood cell counts of 24,000/μL and118,000/μL were reported in two patients in Cohort 3 within 5-8 dayspost-dose. Increase in eosinophils is also expected post-treatment andtypically remains elevated through Day 8. At the injected sites, thefollowing toxicities are likely: pain, necrosis, ulceration andinflammation. At other sites of viral replication (e.g., distanttumors), pain, necrosis, ulceration, and inflammation are possible.

Although highly unlikely and not observed after any treatment orexposure to JX-594, a disseminated vaccinia-associated rash orencephalitis is possible; these complications have been described inapproximately 1 in 10,000 and 1 in 1,000,000 smallpox vaccinerecipients, respectively. Furthermore, a statistically significantincreased risk of myocarditis (1-2 per 10,000 vaccinees) wasdemonstrated in a recent program of vaccinations with the NYCBOHvaccinia strain (Arness et al., 2004).

G. Statistics

1. Outcome Definitions

Following are definitions of the outcomes relative to the statisticalanalyses. Toxicity coding and the definitions of progressive disease,complete response, partial response, duration of overall response,evaluable patient, and treatment-related are discussed elsewhere in theprotocol.

Progression-Free Survival.

Time from first treatment with JX-594 until date of diagnosis ofprogression, as assessed by the investigator, or the date of deathwithout progression. Patients last known to be alive without progressionwill be censored at the time of their last assessment of progression.Patients who receive non-protocol therapy prior to the documentation ofprogressive disease will also be designated as censored in thestatistical analyses.

Overall Survival.

Time from first treatment with JX-594 until the date of death or datelast known to be alive; patients last known to be alive are designatedas censored in statistical analyses.

2. Analysis Sets or Populations

All patients who receive JX-594 will be analyzed for demographiccharacteristics at screening and subsequently for safety, efficacy,pharmacokinetics and pharmacodynamics. The population to be summarizedwill be an intent-to-treat (ITT) population, defined as all patientsreceiving at least one treatment with JX-594. In addition, an evaluablepatient population will also be assessed (a subset of the ITTpopulation). A patient will be considered an evaluable patient if thepatient receives at least one treatment of JX-594 and has appropriatetumor measurement at baseline and at the first appropriate time pointpost-treatment.

3. Method of Analysis

Continuous variables will be summarized using descriptive statistics (n,mean, standard deviation, median, minimum, and maximum). Categoricalvariables will be summarized showing the number and percentage (n, %) ofpatients within each classification. Analyses will be done based onevaluable patients, as well as on the intent-to-treat population.Overall analyses will be conducted; additionally, safety and efficacyanalyses will be correlated with disease staging.

Safety: Methods of Analysis.

Patients who receive any study medication will be included in the safetyanalysis. Safety data including adverse events, laboratory results,toxicity, vital signs and withdrawal information will be summarized overtime. Patient age, weight, and height will be summarized withdescriptive statistics, while gender and race will be summarized withfrequency tabulations. Medical history data will be summarized withfrequency tabulations.

Adverse events will be coded and tabulated using the MedDRAclassification scheme. The incidence of treatment-emergent AEs will betabulated; in addition, the data will be stratified by adverse eventseverity (grade) and investigator-specified relationship to JX-594. Theanalysis of safety will focus on non-hematologic adverse events of Grade3 or 4 and hematologic adverse events of Grade 4. A listing of SAEs willbe produced.

Hematology and serum chemistry results will be summarized usingdescriptive statistics for continuous variables. In addition, a nadiranalysis of selected hematology parameters will be performed andsummarized. Laboratory results will be summarized over time in shifttables displaying the numbers of patients with post-dosing changes frombaseline relative to the reference range. Laboratory results forselected variables will also be displayed graphically.

KPS performance scores will be summarized using descriptive statisticsfor categorical variables. The maximum shift in KPS performance scorescompared with screening and/or baseline may also be summarized. Theremaining safety variables will be summarized using descriptivestatistics.

Pharmacokinetic/Pharmacodynamic: Methods of Analysis.

Over time, viral replication and shedding into the blood will beassessed by following genome concentrations in the blood. Bloodconcentrations of JX-594 and GM-CSF levelswill be measured in allpatients and pharmacokinetic parameters estimated.

The pharmacodynamic parameters to be analyzed will include the effect ofJX-594 and GM-CSF on peripheral blood counts, MIA, and tumor biopsytissue. The immune response to JX-594 following IT injection will beevaluated and summarized, including changes from baseline in white bloodcell subsets (absolute eosinophil count, ANC, lymphocytes), cytokines,and formation of neutralizing antibodies to JX-594.

The change from baseline in histologic endpoints (tumor tissue andnormal tissue control), including inflammatory cell infiltration, viralgene expression, GM-CSF expression, lac-Z expression and tumor necrosiswill be evaluated and summarized. Apoptosis, virus replication factorieswithin the cytoplasm, EGFR pathway status, and tumor thymidine kinasestatus may also be evaluated.

Efficacy: Methods of Analysis.

Treatment response rate based on RECIST criteria will be evaluated forthe following: overall response, injected tumor response, andnon-injected tumor response. Rates of complete response, partialresponse, stable disease, and progressive disease will be summarized.Progression-free survival, time-toprogression, duration of response, andoverall survival will also be reported. Correlation to disease stagingwill be assessed.

Progression free survival and duration of response will be estimatedusing the Kaplan-Meier method. The median, (2-sided) 95% confidenceinterval for the median, minimum, and maximum duration, as well as thenumber of censored patients, will be presented. Descriptive statisticsand curve for progression-free survival will be made. Assessment ofclinical benefit to patients will also be made by evaluation of weightgain and improvement in performance status over time following treatmentwith JX-594. The change over time in the melanoma inhibitory activityprotein (MIA) may be evaluated. MIA may also be compared againsttreatment response.

Independent Review of Response Assessment.

Sites may be asked to provide copies of all radiology data for selectedpatients (digital or CD-ROM preferred) to an independent radiologyreviewer (IRR). For patients with skin lesions, photographs would alsobe sent to the IRR for independent review. Results from both the siteand IRR will be reported. No evaluation of discordance between readerswill be conducted.

Example 7 Treatment of Refractory Liver Tumors

In a Phase I pilot trial of JX-594, seven melanoma patients receivedescalating doses injected into superficial skin metastases (Mastrangeloet aL, 1999). No maximum-tolerated dose (MTD) was reported; tumorresponses were reported. The objectives of the current trial were todefine the following: safety and MTD at significantly higher doses(100-fold), without pre-immunization (as was done in the pilot study),specifically following treatment within a solid organ; pharmacokinetics,including replication-dependent shedding into the blood over threeweeks; efficacy against a broad spectrum of cancer types. In this PhaseI trial the inventors therefore treated patients with liver tumors(primary or metastatic) by intratumoral injection. For the first time,the inventors report an MTD, plus high-level JX-594 replication andsystemic GM-CSF expression, efficacy and distant tumor targeting atwell-tolerated doses. The results reported herein support future i.t.and i.v. trials with JX-594 and products from this class.

A. Materials and Methods

1. Study Design

The primary objective was to determine the safety and MTD of JX-594.Secondary objectives included pharmacokinetics, replication and shedding(urine, throat swabs), immune responses (neutralizing antibodies,cytokines) and tumor responses. Patients received one of four doselevels (10⁸, 3×10⁸, 10⁹, 3×10⁹ plaque-forming units, pfu) in agroup-sequential dose escalation design (2-6 patients per dose level).The MTD was defined as the dose level immediately preceding that forwhich two or more dose-limiting toxicities (DLT) were observed. DLT wasdefined as any grade 4 toxicity, or grade 3 toxicity lasting >5 days. Anindependent Data Safety Monitoring Board (DSMB) reviewed alldose-escalation decisions and major safety assessments.

2. Patient Selection

Patients signed informed consent, according to Good Clinical Practice(GCP) guidelines. Inclusion criteria included unresectable, injectablesolid tumor(s) within the liver that had progressed despite treatmentwith standard therapies, normal hematopoietic function (leukocytecount>3,000 mm³, hemoglobin>10 g/dL, platelet count>75,000/mm³ and organfunction (including creatinine ≦1.5 mg/dL, AST/ALT≦2•5 of ULN,Child-Pugh class A or B), life expectancy≧16 weeks, and KarnofskyPerformance Status (KPS)≧70. Exclusion criteria included increased riskfor vaccination complications (e.g., immunosuppression, eczema),treatment with immunosuppressive or cancer treatment agents within 4weeks, pregnancy, or nursing.

3. Manufacturing and Preparation of JX-594

JX-594 is a Wyeth strain vaccinia modified by insertion of the humanGM-CSF and lacZ genes into the TK gene region under control of thesynthetic early-late promoter and p7•5 promoter, respectively. Clinicaltrial material was generated according to GMP guidelines in Vero cellsand purified through sucrose gradient centrifugation. The genome-to-pfuratio was approximately 70:1. JX-594 was formulated inphosphate-buffered saline with 10% glycerol, 138 mM sodium chloride atpH 7•4. Final product QC release tests included assays for sterility,endotoxin and potency. JX-594 was diluted in 0.9% normal saline in avolume equivalent to 25% of the estimated total volume of targettumor(s).

4. Treatment Procedure

JX-594 was administered via imaging-guided intratumoral injection using21-gauge PEIT (percutaneous ethanol injection, multi-pore; HAKKOMedicals; Tokyo, Japan) needles. Tumors (n=1-3) were injected everythree weeks along two needle tracks during withdrawal of the needlethrough the tumor. The initial treatment course was 2 cycles; up to 6additional cycles were allowed if tumor response occurred.

5. Patient Monitoring

Patients were monitored as described in Table 6. Patients were monitoredafter treatment in the hospital for at least 48 hours, and for fourweeks as out-patients.

TABLE 6 Study Procedures Study Day Day Day 1 Day 1 Day Day Day Day DayEnd of Study −14-0 Pre Post 3 5 8 15 22⁷ Visit/Day 28 JX-594 injection(under x CT-guidance) Clinical Evaluations Physical exam, ECOG x x  x¹ xx x x x x performance status Safety Laboratoty Evaluations²Hematology³/Coagulation x x x x x x x x Serum Chemistries x x x x x x xx Viral Assays Plasma/blood levels of x  x⁴ x x x x x x JX-594: Q-PCRShedding (throat swab, x  x⁴ x x x x urine): plaque assay ImmunologicEvaluations Neutralizing antibodies x x Cytokines (inc. GM-CSF) x  x⁵ xx Pathologic Evaluations Tumor biopsy  x⁶  x⁶  x⁶ Efficacy EvaluationsCT scan x x PET -CT (optional) Serum tumor markers⁸ x x

6. Neutralizing Antibody (NAb) Titers

NAb titers were determined by cytopathic effect inhibition assay.Heat-inactivated serum was serially diluted in media using half logdilutions. 50 μL samples were incubated with 1,000 pfu JX-594 for twohours, then inoculated onto A2780 cells. After 3 days, cell viabilitywas determined using Cell Counting Kit-8 (Donjindo Laboratories,Kumamoto, Japan). NAb titer was defined as the reciprocal of the highestdilution of serum that resulted in ≧50% cell viability.

7. Quantitative PCR for JX-594

Quantitative PCR (Q-PCR) was used to measure JX-594 genomes in bloodserially due to its reproducibility and ability to detect productregardless of antibody and/or complement neutralization. JX-594 DNA waspurified from samples using the QIAamp DNA Blood Mini Kit (Qiagen GmbH,Hilden, Germany). Q-PCR was run as described previously (Kulesh et al.,2004). The lower limits of JX-594 detection and quantitation were 666and 3,333 copies/mL plasma, respectively.

8. JX-594 Shedding Detection

A plaque-forming assay was used to detect any shedding of infectiousJX-594 into the environment; infectious unit shedding would have publichealth relevance. Urine and saliva samples were spun, resuspended in 10mM Tris (pH 9•0), and titered on A2780 cells by plaque assays. Thedetection limit was 20 pfu/ml sample.

9. Cytokine Assays

GM-CSF was detected by ELISA kit (BioSource International; Carlsbad,Calif., USA) following the instructions of the vendor. Serum levels ofIL-1β, IL-6, IL-10, TNF-alpha, and interferon-gamma were assessed usingthe LINCOplex kit as instructed by the manufacturer (LINCO; St. Charles,Mo.).

10. Histopathology Staining for Vaccinia Proteins and LacZ in Blood andTumor Samples

Formalin-fixed, paraffin-embedded biopsies were stained with hematoxylinand eosin for histology. For immunohistochemistry, mouse monoclonalantibodies for B5R (Vac-14, α-B5R, 46 μg/mL; Dr. Gary Cohen, UniversityPennsylvannia; diluted 1: 50 or 1:100) were used, followed by incubationwith DAKO EnVision+™ anti-mouse HRP-labeled polymer (DAKO, Carpinteria,Calif.) prior to development using DAB (Kirkegaard & Perry Laboratories;Gaithersburg, Md.). For LacZ staining, cells were spun at 900 rpm for 1minute, rinsed, and fixed with 0.5% gluteraldehyde on glass slides.Cells were then washed and stained with X-gal solution for 4 hours toovernight.

11. Tumor Response Assessment

Tumor response was assessed after every two cycles. Contrast-enhanced CTscanning was standard (unless contraindicated). Maximum tumor diametersand Hounsfield units (HU; density estimate) were obtained. RECIST andChoi criteria for response were applied (Choi et al., 2007). Tumormarkers were followed if elevated at baseline.

12. Statistical Issues

Study sample size was determined by safety issues. The intent-to-treatpopulation (≧1 dose) and standard dose-escalation design were utilized.The likelihood of dose escalation, given varying true DLT rates in thetreated population, was calculated as per routine in Phase Idose-escalation trials.

B. Results

1. Patient Characteristics

Fourteen patients were enrolled (characteristics listed in Table 7;trial profile in FIG. 34). Three patients were treated in cohorts 1-2,six in the third and two in the highest. Six patients were treated incohort 3 at the request of the DSMB due to an unrelated patient deathattributed to tumor progression. Two patients (cohorts 1, 3) hadtreatment suspended after one cycle due to unrelated adverse events, andpatients at the highest dose received one cycle due to DLT (see below).

TABLE 7 Patient demographics Mean Age (years) 56.5 (37-66) Sex 11 males,3 females Mean previous therapies 5.6 (2-12) Tumor size (cm) 6.9(3.5-9.8) Cycles of JX-594 received 3.4 (1-8) Tumor types Colon (4), HCC(3), melanoma (2), RCC (1), SCC, thymic (1), SCC-lung (1), gastric (1),extragonadal germ cell (1)

2. Treatment-Related Toxicity

a. Adverse Events (AE)

JX-594 was well-tolerated up to the MTD (10⁹ pfu). No treatment-relateddeaths occurred on study. All patients experienced grade 1-2 flu-likesymptoms (from 4-16 hours post-treatment). Dose-related hypotension(grade 2, no organ dysfunction) occurred within 4-12 hours. Table 8lists the most common AEs possibly related to JX-594. Only one seriousAE case (anorexia and abdominal pain) was deemed treatment-related. Tenserious and unrelated (according to the PI) AEs were reported andattributed to tumor progression-associated complications. Four patientsdied from tumor progression during the AE reporting period.

Two patients in cohort 4 experienced DLTs. Both experienced Grade 3direct hyperbilirubinemia due to tumor swelling and obstruction of theintrahepatic bile duct, plus Grade III anorexia and abdominal pain.

b. Laboratory Data

Treatment-related transient decreases in lymphocytes, platelets andhematocrit were noted during the first 3 days. Nine patients had asignificant increase in absolute neutrophil counts (ANC) within thefirst four days (seven increased>100%; FIG. 35A). ANC increases weredose-related and frequently associated with GM-CSF detection in theblood. ANC increased significantly (≧5,000/μL) in 75% of patients incohorts 3 and 4 (versus 17% in cohorts 1, 2; FIG. 35A); increases inmonocytes and eosinophils were observed. Thrombocytopenia was alsodose-dependent (FIG. 36A) but cycle-independent (FIG. 36B). ANCincreases were greatest in cycle 1 (FIG. 36C). Lymphopenia andleukopenia occurred in 2 patients (Table 8). Significant transaminitisdid not occur at the MTD (FIG. 35B).

TABLE 8 Most Common Adverse Events (including Grade 1/2 AEs Experiencedby ≧3 Patients and Grade 3/4 AEs Experienced by ≧1 Patient) possiblyrelated to JX-594 Number of Patients by Cohort Grade 1/2 Grade 3 Grade 4(5) 1 2 3 4 1 2 3 4 1 2 3 4 Total (n = (n = (n = (n = (n = (n = (n = (n= (n = (n = (n = (n = Patients Body System Event 3) 3) 6) 2) 3) 3) 6) 2)3) 3) 6) 2) (n = 14) General Fever 3 3 5 2 1 (14) 100% Chills 3 2 6 2 1(14) 100% Fatigue 2 3 1  (6) 43% Gastrointestinal Anorexia 2 2 5 1 (10)71% Nausea 1 1 1  (3) 21% Nervous Headache 1 1 2  (4) 29% SystemMetabolic/ Hyponatremia 2  (2) 14% Laboratory Alk Phos increased 1 1 (2) 14% Hyperbilirubinemia 1 2  (3) 21% ALT increased 1 1  (2) 14% ASTincreased 1 1  (2) 14% Hypophosphatemia 1  (1) 7% Fibrinogen decrease 11  (2) 14% Hematologic Leukocyte count 2 1 1  (4) 29% increased Plateletcount 1 2  (3) 21% decreased Leukopenia 1 1 1  (3) 21% Neutrophil count2  (2) 14% decreased Pain Pain—general 1 1 2  (4) 29%

3. Pharmacokinetic and Pharmacodynamic Endpoints

a. Serum GM-CSF

Thirteen patients were negative for serum GM-CSF at baseline. Threepatients at the MTD had detectable GM-CSF>48 hours (46-16,000 pg/mL)after JX-594 injection (FIG. 35A), concentrations that were higher thanthose reported following subcutaneous injection of GM-CSF protein inpatients (Cebon et aL, 1992). GM-CSF concentrations correlated with WBCinduction (FIG. 35A).

b. Neutralizing Antibodies (NAb)

Low (<10) or undetectable anti-JX-594 antibody (NAb) levels were notedat baseline in 79% of patients. All patients developed NAb within 22days. NAb titers peaked after the first dose in 45% of patients, andincreased further in 55%.

No correlation was seen between baseline or post-treatment NAb titersand any clinical or laboratory endpoint, including JX-594pharmacokinetics, replication, GM-CSF expression or efficacy. Threepatients with objective RECIST tumor responses had detectable baselineNAb titers and high titers post-treatment (32,000, 32,000, and 10,000).In addition, two patients had newly developed neck metastases treatedafter high-level NAb induction, and both tumors underwent objectiveresponses (below; Table 9 and FIG. 38B).

TABLE 9 Target tumor responses and survival duration Patient (tumortype/ diameter/previous Cohort/ Tumor treatments) cycles RECIST² Choi³PET Marker⁴ Survival⁵ 103 1/6 PR +(↓51% diam) n.a. n.a. 19.8 m⁶ (SCClung/9.8 cm/5) 201 2/8 Liver: PR +(↓30% diam) Liver: neg  PR 11 + m(HCC/6.2 cm/5) Neck: PR +(↓57% diam) Neck: −76% (−98%) 304 3/6 Liver: PR+(↓33% diam) Liver: −29% n.a. 12.2 + m (Melanoma/7.8 cm/3) Neck: SD+(↓51% HU) Neck: −42% 301 3/4 SD + (↓42% HU⁷) +40% n.a. 15.1 m⁶ (RCC/5.7cm/5) 302 3/4 SD + (↓15% HU)  +4% SD 8.9 m (Colon/9.0 cm/6) 202 2/4 SD +(↓16% HU) n.a. n.a. 10.1 m (SCC thymic/ 9.7 cm/4) 102 1/3 SD + (↓31% HU)n.a. n.a. 8.2 m (Colon/4.1 cm/4) 203 2/5 SD + (↓40% HU)  −6% SD 4.5 m(Extragonadal germ/ 6.1 cm/4) 305 3/2 SD − (↑28%) +55% PD 1.8 m(Colon/7.4 cm/5) 306 3/2 PD + (↓33% HU) +56% SD 9.4 m⁶ (Colon/5.8 cm/11)101 1/1  n.a.⁸  n.a.⁸ n.a. n.a. 1.8 m (Gastric/8.5 cm/6) 303 3/1 n. a.n.a. n.a. n.a. 10 d (Melanoma/10.9 cm/7) 401 4/1 n.a. n.a. −41% PR 3 + m(HCC/3.5 cm/12) (−81%) 402 4/1 n.a. n.a. n.a. PR 18 + d (MCC/9.8 cm/2)(−65%) ¹First number reflects dose level (eg. 103 was in dose level 1)²RECIST criteria: partial response (PR) is a maximum diameter decreaseof ≧30%; progressive disease (PD) is an increase of ≧20%; stable diseaseis a change in diameter between these two bounds for PR and PD ³Choicriteria: maximum diameter decrease of ≧10% or density decrease of≧15%; + indicates response ⁴Tumor marker response definition: ≧50%decrease: PR; ≧25% increase: PD; <50% decrease or 25% increase: SD;marker was alpha-fetoprotein (AFP) in patients 201, 301, 402; PIVKA2 for401; carcinoembryonic antigen (CEA) for 302, 305, 306. ⁵Survival: +indicates no cancer-related death; m: months; d: days ⁶still alive ⁷HU:Hounsfield units ⁸CT scans performed at week 3 showed tumor progression

c. Cytokines

Interleukin-6, IL-10, and TNF-α peaked at 3 hours. Later peaks (day3-22) were also observed. Cytokine induction was greater in cycles 2-8than in cycle 1. Interleukin-6 induction correlated with GM-CSF inserum. IL-1β and IL-4 induction were not noted.

d. JX-594 Pharmacokinetics

All patients had JX-594 genomes detected immediately after injection (49of 50 cycles). Concentrations correlated with dose (FIGS. 37A and 37B),decreasing ˜50% within 15 minutes and ˜90% within 4-6 hours. Initialclearance rates were not dose-dependent nor antibody titer-dependent.Following initial release and clearance of injected JX-594 in blood,delayed re-emergence of circulating JX-594 was frequently detected,consistent with replication. Twelve of 15 (80%) patients had detectablegenomes (blood or plasma) between days 3-22. Secondary peakconcentrations generally correlated with dose, and the pharmacokineticswere similar (FIG. 37B). Lower secondary concentration peaks weredetected after repeat dosing in cycles 2-7 (4 of 11 patients).Representative pharmacokinetics are shown in FIG. 37C.

e. JX-594 Dissemination, Replication within Non-Injected Distant TumorSites

JX-594 was detected in non-injected tumor tissues, indicating distanttumor-selective infection and replication (FIG. 37D-F). For example, themalignant ascites and pleural effusion of one patient had higher genomeconcentrations (17- and 12-fold higher, respectively) and GM-CSFconcentrations (24- and 13-fold higher, respectively) than in blood atthe same timepoint (FIG. 37D). LacZ(+) cells in the pleural effusionconfirmed JX-594 infection (FIG. 37E). Another patient had a distantneck tumor biopsied and replicating JX-594 was demonstratedhistologically (FIG. 37F).

f. JX-594 Shedding

No infectious JX-594 was detected in any throat or urine sample.

4. Antitumoral Efficacy of JX-594

Ten patients were evaluable for target tumor responses; non-evaluablepatients had contraindications to contrast (2) or no post-treatmentscans (2). Nine (90%) had either objective response (30%) or stabledisease (60%) by CT RECIST criteria. Eight (80%) had objective responsesby Choi criteria (Table 9). Patients with response by both RECIST andChoi criteria had non-small cell lung cancer (FIG. 38A), HCC andmelanoma (Table 9). Objective responses were durable; regrowth atresponding tumor sites did not occur (4-18 months follow-up). Directinjection of previously non-injected tumors in the neck in two patients,after 4 prior cycles in the liver, led to Choi and/or RECIST responsesdespite high-level neutralizing antibodies to JX-594 (Table 9, FIG.38B); therefore, re-treatment efficacy was feasible.

Responses in distant, non-injected tumors were also assessed. Amongseven patients with distant non-injected tumors, six patients had stabledistant disease by RECIST criteria; the time-to-progression of thesedistant tumors ranged from 6+ to 30+ weeks. Three of these patients hadresponses by Choi criteria (n=2) or PET-CT (n=1; 25-100% decrease; Table10).

TABLE 10 Responses of distant tumors in patients with target tumorcontrol (RECIST PRo r SD) Distant Time to tumor tumor Patient size (cm)/progres (dose gp¹) location RECIST Choi PET -sion² 202  5 · 9/Liver SD +(↓35% HU) n.a. 30+ wks 103  8 · 5/Liver SD + (↓22% HU) n.a. 7+ wks 3047/face, n.a. n.a. CR - SC 6+ wks mediastinum tumor PR - PA tumor 102  4· 3/Liver SD − (↓10% HU) n.a. 9 wks 203  8 · 3/LNs SD − (↑5%)  −6% 15wks (12 wks) 201  3 · 7/Liver SD − (↓6%) SD 18 wks 301 11 · 8/Liver PD −(↑22%) +10% 6 wks ¹First number reflects dose level (e.g. 103 was indose level 1) ²by CT RECIST; + indicates no cancer-related death HU:Hounsfield units; LN: lymph nodes; SC: supraclavicular; PA:preauricular; CR: complete response; PR: partial response; SD: stabledisease; PD: progressive disease

To date, eight patients (57%) have survived for at least 8 months, fourmore than one year and one up to 20+ months. Median survival was 9months.

All of the compositions and/or methods disclosed and claimed herein canbe made and executed without undue experimentation in light of thepresent disclosure. While the compositions and methods of this inventionhave been described in terms of preferred embodiments, it will beapparent to those of skill in the art that variations may be applied tothe compositions and/or methods and in the steps or in the sequence ofsteps of the method described herein without departing from the concept,spirit and scope of the invention. More specifically, it will beapparent that certain agents which are both chemically andphysiologically related may be substituted for the agents describedherein while the same or similar results would be achieved. All suchsimilar substitutes and modifications apparent to those skilled in theart are deemed to be within the spirit, scope and concept of theinvention as defined by the appended claims.

REFERENCES

The following references, to the extent that they provide exemplaryprocedural or other details supplementary to those set forth herein, arespecifically incorporated herein by reference.

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1. A method of inducing oncolysis in a subject having a tumor comprisingadministering to said subject at least one dose of a pharmaceuticalcomposition comprising a pharmaceutically acceptable carrier and apurified TK-deficient, GM-CSF-expressing, replication-competent vacciniavirus vector wherein said dose comprises at least 1×10⁸ pfu and issufficient to induce oncolysis of cells in the tumor.
 2. The method ofclaim 1, wherein the dose comprises at least 1×10⁹ pfu.
 3. The method ofclaim 1, wherein the subject is administered 2 or more doses.
 4. Themethod of claim 3, wherein 2 or more doses are administered over aperiod of at least 7 days.
 5. The method of claim 1, wherein saidsubject is a human.
 6. The method of claim 1, wherein said tumor is abrain cancer tumor, a head & neck cancer tumor, an esophageal cancertumor, a skin cancer tumor, a lung cancer tumor, a thymic cancer tumor,a stomach cancer tumor, a colon cancer tumor, a liver cancer tumor, anovarian cancer tumor, a uterine cancer tumor, a bladder cancer tumor, atesticular cancer tumor, a rectal cancer tumor, a breast cancer tumor,or a pancreatic cancer tumor.
 7. The method of claim 6, wherein thetumor is a hepatocellular carcinoma or a melanoma.
 8. The method ofclaim 1, wherein oncolysis is induced in 20% to 90% of cells in saidtumor.
 9. The method of claim 1, wherein said tumor is recurrent. 10.The method of claim 1, wherein said tumor is primary.
 11. The method ofclaim 1, wherein said tumor is metastatic.
 12. The method of claim 1,wherein said tumor is multi-drug resistant.
 13. The method of claim 1,further comprising administering to said subject a second cancertherapy.
 14. The method of claim 1, further comprising a second cancertherapy selected from chemotherapy, biological therapy, radiotherapy,immunotherapy, hormone therapy, ant-vascular therapy, cryotherapy, toxintherapy or surgery.
 15. The method of claim 1, wherein said subject isimmunocompromised.
 16. The method of claim 1, wherein said tumor isnon-resectable prior to treatment and resectable following treatment.17. The method of claim 1, further comprising assessing tumor cellviability following treatment.
 18. The method of claim 1, whereinadministering comprises injection into tumor mass.
 19. The method ofclaim 1, wherein administering comprises injection into tumorvasculature.
 20. The method of claim 1, wherein administering comprisesinjection into a lymphatic or vasculature system regional to said tumor.